A synthesis of 1-lithiated glycals and 1-tributylstannyl glycals from 1-phenylsulfinyl glycals via sulfoxide-lithium ligand exchange

Article abstract of DOI:10.1055/s-2008-1067226

1-Lithiated glycals generated by reaction of 1-phenyl-sulfinyl glycals with either t-BuLi or PhLi are transformed to 1-tributylstannyl glycals on reaction with tributyltin chloride. Georg Thieme Verlag Stuttgart.

Full text of DOI:10.1055/s-2008-1067226

PAPER
2747
A Synthesis of 1-Lithiated Glycals and 1-Tributylstannyl Glycals from
1-Phenylsulfinyl Glycals via Sulfoxide–Lithium Ligand Exchange
1
-Tributylstannyl
r
lycals
f
z
rom1-Phe
y
G
s
lycals ztof Jarowicki, Colin Kilner, Philip J. Kocienski,* Zofia Komsta, Jacqueline E. Milne, Anna Wojtasiewicz,
Victoria Coombs
Institute of Process Research and Development, School of Chemistry, Leeds University, Leeds, LS2 9JT, UK
E-mail: p.j.kocienski@leeds.ac.uk
Received 5 May 2008
t-BuLi in THF at –78 °C followed by quenching with
Bu3SnCl (Scheme 2). The lithiation conditions, first de-
scribed by Boeckman and Bruza18 are harsh,19 and some
common protecting groups such as benzyl and tert-bu-
tyldimethylsilyl (TBS) ethers may undergo competing
lithiation.20,21 However, even when the protected ethers
are inert under the reaction conditions, their presence may
require 3–6 equivalents of t-BuLi to complete the lithia-
tion, presumably due to complexation effects. For exam-
ple, C1 lithiation of D-galactal derivative 5 requires 3.5
equivalents of t-BuLi (and a corresponding excess of
Bu3SnCl) in order to obtain a yield of 85% of stannane 6
(Scheme 2).22 The same sequence on 3,4,6- tri-O-tert-bu-
tyldimethylsilyl-D-glucal delivers only 12–30% of the
stannane.20 Protecting groups that survive the metallation
of glycals by t-BuLi are MOM,7,23 TBDPS,7,12,20,22,24
TIPS,7,14,22,25 di-tert-butylsilylene,7,24 TBS (except when it
is located at C6),4,22,26 and isopropylidene6,22 as illustrated
by the examples shown in Scheme 2.
Abstract: 1-Lithiated glycals generated by reaction of 1-phenyl-
sulfinyl glycals with either t-BuLi or PhLi are transformed to 1-
tributylstannyl glycals on reaction with tributyltin chloride.
Keywords: lithium, tin, sulfoxides, carbohydrates, glycals
1-Tributylstannyl glycals (e.g., 1) are versatile reagents
for the formation of C–C bonds at C1 of carbohydrates (C-
glycosidation).1 For example, they undergo Pd(0)-cata-
lysed Stille cross-coupling reactions with aryl halides
(Scheme 1),2–5 alkenyl halides,6 enol triflates,7 acyl ha-
lides, and sulfonyl chlorides.8 Equally important, they
transmetallate easily with n-BuLi to the corresponding
1-lithiated glycals9 (e.g., 3), which participate in diverse
nucleophilic substitutions (e.g., 3 to 4),10,11 nucleophilic
additions,12,13 benzannulation reactions,14,15 and 1,2-
metallate rearrangements.16
TIPSO
OTIPS
TIPSO
OTIPS
TIPSO
TIPSO
n-BuLi (1.0 equiv)
THF, –78 °C, 10 min
TBSO
OTIPS
TBSO
OTIPS
1. t-BuLi (3.5 equiv)
THF, –78 °C; 0 °C
TBSO
TBSO
O
O
O
2. Bu3SnCl (3.5 equiv)
–78 °C, 20 min
O
SnBu3
Li
85% (5.0 mmol scale)22
1
3
H
SnBu3
ROTf (1.0 equiv)
–78 to 0 °C
5
6
41% from 1
ArBr, Pd(0)
t-Bu t-Bu
Si
TIPSO
OTIPS
TIPSO
OTIPS
O
O
O
O
MOMO
TIPSO
OTIPS
TIPSO
TIPSO
TIPSO
TIPSO
O
O
O
O
O
BnO
BnO
SnBu3
7 (86%)22
(3.5 equiv t-BuLi)
SnBu3
8 (90%)7
SnBu3
9 (71%)7
(5.0 equiv t-BuLi)
OAc
O
O
(6.0 equiv t-BuLi)
O
OBn
2
4
TBSO
TBDPSO
TBDPSO
OTBDPS
O
O
TBSO
Scheme 1
O
O
O
Three general syntheses of 1-tributylstannyl glycals have
been reported to date.17 The first and shortest synthesis
entails direct lithiation of a suitably protected glycal with
SnBu3
SnBu3
SnBu3
11 (71%)20
(6.0 equiv t-BuLi)
12 (89%)6
(1.5 equiv t-BuLi)
10 (92%)4
(2.0 equiv t-BuLi)
Scheme 2
SYNTHESIS 2008, No. 17, pp 2747–2763
x
x.
x
x
.
2
0
0
8
Advanced online publication: 13.08.2008
DOI: 10.1055/s-2008-1067226; Art ID: Z10208SS
© Georg Thieme Verlag Stuttgart · New York

2748
K. Jarowicki et al.
PAPER
The second route to 1-tributylstannyl glycals, devised by We recently reported a synthesis of D-erythro-sphin-
Beau and co-workers,3,27 is longer, but it is compatible gosine that featured a 1,2-metallate rearrangement of the
with the ubiquitous benzyl ether and benzylidene acetal 1-lithiated glycal 24 prepared by a novel route
protecting groups because it avoids the use of harsh met- (Scheme 5).16 A key reaction of the sequence entailed
allating conditions. The key step is a radical substitution treatment of the stable, storable sulfoxide 23 with t-BuLi
on a 1-phenylsulfonyl glycal (e.g., 13) by a tributylstannyl at –78 °C whereupon a rapid phenylsulfinyl–lithium ex-
group at elevated temperature (Scheme 3). Unfortunately, change occurred to generate the 1-lithiated glycal 24. We
the reaction requires an excess of Bu3SnH (≥2.5 equiv) reasoned that this reaction, coupled to stannylation with a
and even then, it does not go to completion.
slight excess of tributyltin chloride,10 the cheapest of the
tributyltin reagents, would provide a convenient access to
1-tributylstannyl glycals. Thus treatment of 23 with t-
BuLi (1.2 equiv) for 30 minutes at –78 °C followed by ad-
dition of Bu3SnCl (1.3 equiv) and gradual warming to
room temperature gave the 1-tributylstannyl glycal 19 in
78% yield on a 10 mmol scale after chromatographic pu-
rification.
OBn OBn
OBn OBn
BnO
BnO
Bu3SnH (2.5 equiv)
O
O
AIBN, PhMe, 110 °C
77% (21% rsm)
SO2Ph
13
SnBu3
14
Ph
Ph
OTBS
OTBS
t-BuLi (1.2 equiv)
Et2O–THF, –78 °C
BnO
TBSO
TBSO
O
O
O
O
BnO
TBSO
BnO
O
O
– PhS(O)t-Bu
O
O
O
S
Li
Ph
O
SnBu3
15 (71%, 26% rsm)
SnBu3
16 (52%, 45% rsm)
SnBu3
24
OTBS
(SS)-23
17 (40%)
TBSO
Bu3SnCl (1.3 equiv)
Scheme 3
–78 °C to r.t., 12 h
78% from 23
O
SnBu3
The 1-phenylsulfonyl glycal substrates at the heart of the
Beau protocol are stable, usually crystalline and easy to
prepare on large scale and these winning features are pre-
served in the third route exemplified by the conversion of
18 to 19 (Scheme 4) in which substitution of a phenylsul-
fonyl group by a tributylstannyl group was accomplished
by a Ni(0)-catalysed coupling reaction.28 The reaction is
scalable and efficient, but it requires 2 equivalents of
Bu3SnMgBr; hence, there are ≥3 equivalents of tin waste
for every equivalent of product formed.29 The conditions
are sufficiently gentle to be applicable to the synthesis of
the sensitive dihydrofuran 22, which is prone to elimina-
tion to the corresponding furan.
19
Scheme 5
In order to broaden the scope and generality of the sulfox-
ide-lithium exchange and stannylation sequence, a further
four 1-phenylsulfinyl glycals were prepared using stan-
dard methods (see Experimental) and converted to the
corresponding 1-tributylstannyl glycals (Scheme 6) in
56–80% yield. A significant improvement arising from
these studies over our Ni(0)-catalysed coupling reaction28
was the reduction in the number of equivalents of Sn from
4 to 1.3 making the procedure much more atom efficient.
Moreover, the speed of the sulfoxide–lithium exchange
was sufficient to consume the t-BuLi before it could cause
mischief. Thus, the synthesis of stannane 20 (Scheme 6)
was accomplished in 62% overall yield from 1-phenyl-
sulfinyl glycal derivative 25 whereas Dötz and co-
workers22 attempted to generate stannane 20 (Scheme 7)
by a direct metallation of glycal 31 (t-BuLi, Bu3SnCl), but
the yield was low (33%) because of competing elimina-
tion to the aldehyde 32 (52%). Similarly, attempts to gen-
erate the furanoid stannane 35 by direct metallation of
glycal 33 with t-BuLi5 resulted in elimination to the furan
34.30 By contrast, our method delivered the analogous
sensitive stannane 30 from the 1-phenylsulfinyl glycal 29
in 56% yield, although in this case 2 equivalents of t-BuLi
were necessary because with 1.2 equivalents of t-BuLi,
the stannane 30 was isolated in only 7% yield.
OTBS
OTBS
Bu3SnMgBr⋅LiBr (2 equiv)
Ni(0) (10 mol%), PPh3
TBSO
TBSO
O
O
THF–Et2O, –78 to 20 °C
95% (17.5 mmol scale)
SnBu3
SO2Ph
18
19
O
O
O
OTBS
TBSO
O
TBSO
TBSO
H
O
O
O
SnBu3
SnBu3
SnBu3
21 (97%)
20 (87%)
22 (68%)
Scheme 4
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2749
Ph
Ph
O
O
S
O
1. t-BuLi (1.2 equiv)
Et2O–THF
30 min, –78 °C
O
O
O
S
O
O
O
1. PhLi (1.2 equiv)
THF, –78 °C, 5 min
TBSO
TBSO
TBSO
TBSO
2. Bu3SnCl (1.3 equiv)
–78 °C, 2 h
87% (3.0 mmol scale)
O
O
O
2. Bu3SnCl (1.3 equiv)
–78 °C to r.t., 12 h
62% (2.57 mmol scale)
O
O
SnBu3
SnBu3
Ph
Ph
20
15
(SS)-25
OTBS
(RS)-36
OTBS
BnO
OBn
BnO
OBn
1. t-BuLi (1.2 equiv)
Et2O–THF
30 min, –78 °C
1. PhLi (1.2 equiv)
THF, –78 °C, 5 min
TBSO
TBSO
BnO
BnO
O
O
O
O
O
2. Bu3SnCl (1.3 equiv)
–78 °C, 2 h
85% (1.0 mmol scale)
2. Bu3SnCl (1.3 equiv)
–78 °C to r.t., 12 h
80% (3.0 mmol scale)
S
SnBu3
S
SnBu3
Ph
Ph
O
27
38
(RS)-26
(SS)-37
OTBS
OTBS
1. t-BuLi (1.2 equiv)
Et2O–THF
30 min, –78 °C
BnO
OBn
BnO
OBn
TBSO
TBSO
1. PhLi (1.2 equiv)
THF, –78 °C, 5 min
BnO
BnO
O
S
O
O
O
2. Bu3SnCl (1.3 equiv)
–78 °C, 2 h
89% (1.0 mmol scale)
2. Bu3SnCl (1.3 equiv)
–78 °C to r.t., 12 h
79% (2.0 mmol scale)
SnBu3
Ph
O
S
SnBu3
Ph
O
21
14
(SS)-28
(SS)-39
TBSO
TBSO
TBSO
TBSO
1. t-BuLi (2.0 equiv)
Et2O–THF
Scheme 8
30 min, –78 °C
O
O
nanes 14, 15, and 38 (Scheme 8) in 85–89% yield cleanly
and reproducibly.
2. Bu3SnCl (2.2 equiv)
–78 °C to r.t., 12 h
56% (3.0 mmol scale)
S
SnBu3
Ph
O
A mechanism for the ligand exchange involving sulfoxide
(SS)-23 and t-BuLi is given in Scheme 9. Oxygen-assisted
attack of the t-BuLi at sulfur from the back side of the
more electronegative glycal ligand forms an unstable trig-
onal bipyramidal s-sulfurane 40a, which can fragment
with expulsion of the 1-lithio glycal 24 and (SS)-42.31 An
alternative mechanism based on some deuteration studies
by Theobald and Okamura32 entails pseudorotation of 40a
to 40b placing both electronegative groups in their
favoured axial positions. Transfer of the lithium from
oxygen to the equatorial lone pair juxtaposes the lithium
and the glycal ligands in intermediate 41 in preparation
for fragmentation to the 1-lithioglycal 24.
30
(SS,RS)-29 (dr 1.4:1)
Scheme 6
O
O
O
O
O
O
TBSO
TBSO
TBSO
1. t-BuLi
+
O
O
2. Bu3SnCl
O
SnBu3
31
32 (52%)
20 (33%)
TBDPSO
TBDPSO
TBDPSO
TBDPSO
TBDPSO
In conclusion, the reaction of t-BuLi or PhLi with 1-phe-
nylsulfinyl glycals provides fast tin-free access to 1-lithi-
ated glycals. In contrast to the direct lithiation procedure
(see Scheme 2), the sulfoxide–lithium exchange requires
only a slight excess of t-BuLi or PhLi and occurs rapidly
at low temperature – conditions that are compatible with
TBS ethers, benzyl ethers, and benzylidene acetals. The
requisite 1-phenylsulfinyl glycals are stable and easily
prepared in quantity from commercial carbohydrates in 6–
8 steps depending on the protecting group regime re-
quired. Finally, the synthesis of 1-tributylstannyl glycals
by reaction of 1-lithiated glycals with Bu3SnCl (1.3 equiv
Sn) is more atom efficient than the routes based on 1-phe-
nylsulfonyl glycals; that is, the radical substitution route
(Scheme 3) and the Ni(0)-catalysed coupling route
(Scheme 4) requiring ≥2.5 and 4 equivalents of Sn, re-
1. t-BuLi
O
O
O
2. Bu3SnCl
SnBu3
SnBu3
33
35
34
Scheme 7
Use of t-BuLi to effect sulfoxide–lithium exchange was
capricious and messy with substrates bearing benzylidene
acetal or benzyl ether protecting groups and we suspected
that competing metallation of the benzyl ethers was to
blame. However, by using the less basic PhLi in THF in-
stead of t-BuLi in Et2O–THF, and shortening the reaction
time to just 5 minutes, we were able to generate the stan-
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2750
K. Jarowicki et al.
PAPER
parenthesis, by the peak intensity relative to the base peak (100%).
Mass spectra were recorded on samples judged to be ≥95% pure by
1H and 13C NMR spectroscopy unless otherwise stated.
OTBS
OTBS
O
OTBS
O
TBSO
TBSO
+ t-BuLi
– t-BuLi
TBSO
O
O
Crystal structure determinations were performed either on a Nonius
KappaCCD diffractometer [(SS)-44, (RS)-36 and (SS)-28]
(Figures 1, 2, 5, respectively) or a Bruker-Nonius X8 Apex/FR591
rotating anode diffractometer [(RS)-48, (RS)-55, (SS)-37 and (SS)-61]
(Figures 3, 4, 7, 6, respectively).40 In all cases: Mo-Ka radiation
and a graphite monochromator were used. T = 150(2) K. For all
structures, anomalous dispersion effects were sufficient to deter-
mine the absolute configuration from the X-ray data since the Flack
parameter refined to zero within accepted limits of error. The struc-
tures were solved by direct methods and refined by the full matrix
least squares method using SHELXS and SHELXL software. Crys-
tallographic data for the structures in this paper have been deposited
at the Cambridge Crystallographic Data Centre as supplementary
publication nos. CCDC 685328 [(SS)-44], 676297 [(RS)-36],
676296 [(RS)-48], 676300 [(RS)-55], 676298 [(SS)-28], 676301
[(SS)-61], 682926 [(SS)-37]. Copies of these data can be obtained,
free of charge, on application to CCDC, 12 Union Road, Cambridge
CB2 1EZ, UK; fax: +44(1223)336033 or e-mail: deposit@-
ccdc.cam.ac.uk or via www.ccdc.cam.ac.uk/conts/retrieving.html.
Li
pseudo-
rotation
S
S
O
S
Ph
Ph
t-Bu
Ph
t-Bu
40a
OLi
40b
(SS)-23
OTBS
O
OTBS
O
TBSO
TBSO
Ph
t-Bu
S
+
O
Li
Li
Ph
S
(SS)-42
t-Bu
O
41
24
Scheme 9
spectively. Our method expands the scope of sulfoxide–
metal ligand exchange reactions, which have hitherto
been used to generate aryllithiums,33 1-chloroalkenylmag-
nesiums,34 chloroalkyllithiums,35 chloroalkylmagne-
Phenylsufinyl–Lithium Exchange and Stannylation Reactions
1,5-Anhydro-2-deoxy-3,4-bis-O-(tert-butyldimethylsilyl)-1-C-
(tributylstannyl)-D-threo-pent-1-enitol (19); Typical Procedure
1 (Schemes 5 and 6)
siums,36 oxiranyllithiums,37 aziridinyllithiums,37 and 1- To a solution of the sulfoxide (SS)-23 (4.68 g, 10.0 mmol) in Et2O
glycosyllithiums.38
(50 mL) and THF (1.60 mL, 20 mmol), at –78 °C, t-BuLi (6.7 mL,
1.8 M, 12 mmol) was added dropwise. The reaction mixture was
maintained at –78 °C for 30 min. and then freshly distilled Bu3SnCl
Where appropriate, solvents and reagents were dried by distillation
from the usual drying agents prior to use: diethyl ether and tetrahy-
drofuran from sodium/benzophenone; dichloromethane and toluene
from calcium hydride; diisopropylethylamine, pyridine and triethyl-
amine from potassium hydroxide. The titre of lithium reagents was
determined by the method of Lipton.39 All reactions were magneti-
cally stirred and were monitored by thin layer chromatography
(TLC) using SiO2 on pre-coated aluminium foil sheets, layer thick-
ness 0.25 mm. Compounds were visualised by UV light (254 and
366 nm) and 20% phosphomolybdic acid in ethanol w/v. Column
chromatography was performed on silica gel 60 (35–70 micron).
Optical rotations were recorded on an Optical Activity AA-1000
polarimeter (units in 10–1 deg·cm2·g–1). IR spectra were recorded on
a Perkin Elmer Spectrum One FT-IR spectrometer as thin films sup-
ported on sodium chloride plates or on a diffuse reflectance sam-
pling cell. Absorptions are reported as values in cm–1 followed by
(4.24 g, 3.53 mL, 13 mmol) was added dropwise. The mixture was
left in the cooling bath and allowed to warm gradually to r.t. over 12
h and then quenched with sat. aq NaHCO3 (50 mL).The mixture was
extracted with Et2O (2 × 50 mL) and the combined organic layers
were dried (Na2SO4) and concentrated in vacuo. The residue was
purified by column chromatography (SiO2, hexanes–Et2O with
0.5% Et3N) to give the stannane 19 (4.97 g, 7.83 mmol, 78%) as a
colourless oil. The 1H and 13C NMR spectroscopic data were iden-
tical to those reported previously.28
1,5-Anhydro-2-deoxy-4-O-tert-butyldimethylsilyl-4,6-O-isopro-
pylidene-1-C-tributylstannyl-D-lyxo-hex-1-enitol (20)
Sulfoxide–lithium exchange of (SS)-25 (1.09 g, 2.6 mmol) with
t-BuLi (1.74 mL, 1.77 M, 3.1 mmol) in Et2O (12.9 mL) and THF
(0.41 mL, 5.14 mmol) followed by quenching with Bu3SnCl (1.09
g, 3.34 mmol) according to typical procedure 1 gave the stannane
20 (0.94 g, 1.6 mmol, 62%) as a colourless oil after purification by
1
the relative intensity: s = strong, m = medium, w = weak. H and
13C NMR spectra were recorded on Brüker DPX300 or DRX500
Fourier Transform spectrometers using an internal deuterium lock.
The chemical shift in ppm is quoted relative to the residual signals
of chloroform (dH = 7.26, dC = 77.4), methanol (dH = 3.34, dC = 49.9)
or benzene (dH = 7.15, dC = 128.6) as the internal standard unless
1
column chromatography on SiO2. The H and 13C NMR spectro-
scopic data were identical to those reported previously.28
1,5-Anhydro-2-deoxy-3,4-di-O-tert-butyldimethylsilyl-1-C-
tributylstannyl-D-erythro-pent-1-enitol (27)
1
otherwise specified. Multiplicities in the H NMR spectra are de-
Sulfoxide–lithium exchange of (RS)-26 (1.41 g, 3.0 mmol) with
t-BuLi (2.1 mL, 1.7 M, 3.6 mmol) in Et2O (15 mL) and THF (0.48
mL, 6.0 mmol) followed by quenching with Bu3SnCl (1.27 g, 3.9
mmol) according to typical procedure 1 gave the stannane 27 (1.53
g, 2.4 mmol, 80%) as a colourless oil after purification by column
chromatography on SiO2.
[a]D21 +128.9 (c 1.36, C6H6).
IR (film): 2929m, 1597s, 1463s, 1252s cm–1.
scribed as: s = singlet, d = doublet, t = triplet, q = quartet,
quin = quintet, m = multiplet, br = broad, and app = apparent. Cou-
pling constants (J) are reported in Hz. The numbers of protons at-
tached to carbon in the 13C NMR spectra were revealed by the
DEPT spectral editing technique. Signal assignments were based on
COSY, HMQC and HMBC correlations. Mass spectrometry was
carried out on a VG autospec mass spectrometer, operating at 70
eV, using electron impact ionisation (EI). Electrospray ionisation
(ES) was performed on either a Micromass LCT TOF spectrometer
or a Waters-Micromass ZMD spectrometer. High-resolution mass
spectrometry (HRMS) was obtained by peak matching using per-
fluorokerosene or reserpine as a standard. Ion mass/charge (m/z)
ratios are reported as values in atomic mass units followed, in
1H NMR (500 MHz, CDCl3): d = 4.78 (1 H, d, J = 5.4 Hz, JSn–H
=
26.1 Hz, C2H), 3.94 (1 H, ddd, J = 5.4, 3.1, 1.3 Hz, C3H), 3.83 (1
H, ddd, J = 10.8, 3.2, 2.8 Hz, C4H), 3.79 (1 H, dd, J = 10.8, 8.6 Hz,
C5HAHB), 3.64 (1 H, ddd, J = 8.3, 2.8, 1.5 Hz, C5HAHB), 1.61–1.41
(6 H, m, 3 CH2), 1.31 (6 H, app sextet, J = 7.3 Hz, 3 CH2CH3), 0.95–
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2751
0.90 (6 H, m, 3 CH2Sn), 0.90 [9 H, s, (CH3)3C], 0.89 [9 H, s,
(CH3)3C], 0.89 (9 H, t, J = 7.7 Hz, 3 CH3), 0.07 (6 H, s, 2 CH3Si),
0.07 (3 H, s, CH3Si), 0.06 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 164.8 (C1), 113.8 (C2H), 69.2
(C4H), 65.5 (C5H2), 65.0 (C3H), 29.5 (JSn–C = 20.7 Hz, 3 CH2CH3,),
27.6 (JSn–C = 55.7 Hz, 3 CH2CH2CH3), 26.35 [(CH3)3C], 26.33
[(CH3)3C], 18.6 [2 C(CH3)3], 14.1 (3 CH3CH2), 10.0 (JSn–C = 345.7,
330.3 Hz, 3 CH2Sn), –3.7 (CH3Si), –3.9 (2 CH3Si), –4.4 (CH3Si).
mmol) as a colourless oil, which solidified on standing, and the
1
stannane 15 (1.66 g, 2.61 mmol, 87%) as a colourless oil. The H
and 13C NMR spectroscopic data were identical to those reported
previously.28
1,5-Anhydro-2-deoxy-3,4,6-O-phenylmethyl-1-C-tributylstan-
nyl-D-lyxo-hex-1-enitol (38)
Stannane 38 (colourless oil) was synthesised in 85% yield on a 1.0
mmol scale according to typical procedure 2.
HRMS (ES+): m/z calcd for C29H62O328Si2120SnNa (M + Na)+:
657.3133; found: 657.3157.
[a]D23 –42 (c 0.914, CHCl3).
IR (film): 2955m, 2924m, 1602m, 1454m, 1094m, 733m, 696m
cm–1.
1,5-Anhydro-2,6-dideoxy-3,4-di-O-tert-butyldimethylsilyl-1-C-
tributylstannyl-L-arabino-hex-1-enitol (21)
1H NMR (500 MHz, CDCl3): d = 7.34–7.24 (15 ArH, m), 4.87 (1 H,
d, J = 12.0 Hz, CHAHBPh), 4.85 (1 H, d, J = 3.0 Hz, JSn–H = 27.3,
20.5 Hz, C2H), 4.65 (2 H, s, CH2Ph), 4.63 (1 H, d, J = 12.4 Hz,
CHAHBPh), 4.52 (1 H, d, J = 12.0 Hz, CHAHBPh), 4.44 (1 H, d, J =
12.0 Hz, CHAHBPh), 4.17 (1 H, app dt, J = 6.1, 2.7 Hz, C5H), 4.12
(1 H, t, J = 3.6, C3H), 3.95 (1 H, t, J = 3.6 Hz, C4H), 3.78 (1 H, dd,
J = 6.4, 10.3 Hz, C6HAHB), 3.75 (1 H, dd, J = 6.0, 10.0 Hz,
C6HAHB), 1.54–1.48 (6 H, m, 3 CH2CH2CH3), 1.30 (6 H, sextet, J =
7.4 Hz, 3 CH2CH3), 0.96–0.92 (6 H, m, 3 CH2Sn), 0.87 (9 H, t, J =
7.3 Hz, 3 CH3CH2).
13C NMR (75 MHz, CDCl3): d = 164.5 (C1), 139.3 (CAr), 138.8
(CAr), 128.7 (3 CArH), 128.6 (2 CArH), 128.1 (2 CArH), 128.0 (2
CArH), 127.92 (CArH), 127.87 (2 CArH), 127.8 (2 CArH), 127.7 (2
CArH), 110.7 (C2H), 76.2 (C5H), 73.8 (CH2), 73.1 (CH2), 72.5
(C4H), 71.2 (CH2), 71.1 (C3H), 69.2 (C6H2), 29.3 (JSn–C = 20.6 Hz,
3 CH2CH3), 27.6 (JSn–C = 56.0 Hz, 3 CH2CH2CH3), 14.1 (3
CH3CH2), 10.1 (3 CH2Sn). Signals for 2 carbons in the aromatic re-
gion could not be distinguished.
Sulfoxide–lithium exchange of (SS)-28 (0.97 g, 2.0 mmol) with t-
BuLi (1.4 mL, 1.7 M, 2.4 mmol) in Et2O (10 mL) and THF (0.32
mL, 4.0 mmol) followed by quenching with Bu3SnCl (0.85 g, 2.6
mmol) according to typical procedure 1 gave the stannane 21 (1.02
g, 1.6 mmol, 79%) as a colourless oil after purification by column
chromatography on SiO2. The 1H and 13C NMR spectroscopic data
were identical to those reported previously.28
1,4-Anhydro-2-deoxy-3,5-di-O-tert-butyldimethylsilyl-1-C-
tributylstannyl-D-erythro-pent-1-enitol (30)
Sulfoxide–lithium exchange of (SS,RS)-29 (1.40 g, 3.0 mmol, 1.4:1
mixture of sulfoxide epimers) with t-BuLi (3.2 mL, 1.86 M, 6.0
mmol) in Et2O (15 mL) and THF (0.96 mL, 12.0 mmol) followed
by quenching with and Bu3SnCl (2.15 g, 6.6 mmol) according to
typical procedure 1 gave stannane 30 (1.06 g, 1.7 mmol, 56%) as a
colourless oil after purification by column chromatography on basic
Al2O3 deactivated with 5% of H2O eluting with hexanes–Et2O con-
taining 0.5% of Et3N.
HRMS (ES+): m/z calcd for C39H55O4Sn (M + H)+:707.3117; found:
707.3103.
[a]D28 +83 (c 1.2, C6H6).
IR (film): 2956s, 2929s, 2857s, 1577w, 1463m, 1252s, 1076s, 835s
cm–1.
Anal. Calcd for C39H54O4Sn: C, 66.39; H, 7.71. Found: C, 66.6; H,
7.85.
1H NMR (500 MHz, C6D6): d = 5.36 (1 H, d, J = 2.5 Hz, JSn–H = 10.1
Hz, C2H), 5.10 (1 H, t, J = 2.5 Hz, C3H), 4.59 (1 H, ddd, J = 7.3,
5.5, 2.6 Hz, C4H), 3.78 (1 H, dd, J = 10.4, 5.5 Hz, C5HAHB), 3.55
(1 H, dd, J = 10.4, 7.1 Hz, C5HAHB), 1.72–1.53 (6 H, m, 3
CH2CH2CH3), 1.36 (6 H, app sextet, J = 7.3 Hz, 3 CH2CH3), 1.08–
1.03 (6 H, m, 3 CH2Sn), 0.99 [9 H, s, (CH3)3C], 0.96 (9 H, s,
[CH3)3C], 0.93 (9 H, t, J = 7.3 Hz, 3 CH3CH2), 0.17 (3 H, s, CH3Si),
0.16 (3 H, s, CH3Si), 0.06 (3 H, s, CH3Si), 0.05 (3 H, CH3Si).
1,5-Anhydro-2-deoxy-3,4,6-O-phenylmethyl-1-C-tributylstan-
nyl-D-arabino-hex-1-enitol (14)
Stannane 14 was synthesised in 89% yield on a 1.0 mmol scale ac-
cording to typical procedure 2.
[a]D20 –10 (c 1.02, CHCl3).
IR (film): 2955s, 2926s, 1454m, 1072s, 1028m, 734s, 696s cm–1.
13C NMR (75 MHz, C6D6): d = 168.6 (C1), 116.3 (JSn–C = 55.8 Hz,
C2H), 90.8 (C4H), 77.9 (C3H), 64.0 (C5H2), 30.0 (JSn–C = 21.7 Hz,
3 CH2CH3), 28.2 (JSn–C = 56.7 Hz, 3 CH2CH2Sn), 26.73 [(CH3)3C],
26.71 [(CH3)3C], 19.2 [C(CH3)3], 18.9 [C(CH3)3], 14.5 (3 CH3CH
2), 10.6 (JSn–C = 353.6, 338.0 Hz, 3 CH2Sn), –3.3 (CH3Si), –3.4
(CH3Si), –4.6 (CH3Si), –4.7 (CH3Si).
1H NMR (300 MHz, CDCl3): d = 7.34–7.27 (15 ArH, m), 4.84 (1 H,
d, J = 2.3 Hz, JSn–H = 28.7, 23.8 Hz, C2H), 4.85 (1 H, d, J = 11.3 Hz,
CHAHBPh), 4.70 (1 H, d, J = 11.3 Hz, CHAHBPh), 4.65 (1 H, d, J =
11.8 Hz, CHAHBPh), 4.62 (1 H, d, J = 12.0 Hz, CHAHBPh), 4.59 (1
H, d, J = 11.5 Hz, CHAHBPh), 4.57 (1 H, d, J = 12.3 Hz, CHAHBPh),
4.25–4.22 (1 H, m, C3H), 3.90–3.75 (4 H, m, C4H, C5H, C6H2),
1.58–1.50 (6 H, m, 3 CH2CH2CH3), 1.31 (6 H, sextet, J = 7.4 Hz, 3
CH2CH3), 0.98–0.93 (6 H, m, 3 CH2Sn), 0.88 (9 H, t, J = 7.4 Hz, 3
CH3CH2).
HRMS (ES+): m/z calcd for C29H62O3Si2SnNa (M + Na)+: 657.3152;
found: 657.3154.
13C NMR (75 MHz, CDCl3): d = 165.3 (C1), 139.1 (CAr), 139.0
(CAr), 128.7 (4 CArH), 128.6 (2 CArH), 128.3 (2 CArH), 128.1 (2
CArH), 128.0 (CArH), 127.9 (CArH), 127.8 (2 CArH), 127.8 (CArH),
111.3 (C2H), 77.9 (CH), 77.8 (CH), 75.3 (CH), 74.2 (CH2), 73.8
(CH2), 70.7 (CH2), 69.4 (C6H2), 29.3 (JSn–C = 20.6 Hz, 3
CH2CH2CH3), 27.6 (JSn–C = 44.6 Hz, 3 CH2CH3), 14.1 (3 CH3CH2),
10.1 (JSn–C = 84.5 Hz, 3 CH2Sn). A signal for 1 carbon in the aro-
matic region could not be distinguished.
1,5-Anhydro-2-deoxy-3-O-tert-butyldimethylsilyl-4,6-O-[(R)-
phenylmethylene]-1-C-tributylstannyl-D-arabino-hex-1-enitol
(15); Typical Procedure 2 (Scheme 8)
To a solution of the sulfoxide (RS)-36 (1.42 g, 3.0 mmol) in THF
(20.0 mL), at –78 °C was added dropwise a solution of PhLi in
Bu2O (2.0 mL, 1.78 M, 3.6 mmol). The reaction mixture was main-
tained at –78 °C for 5 min and then Bu3SnCl (1.27 g, 1.1 mL, 3.9
mmol) was added dropwise. After addition was complete, the mix-
ture was stirred at –78 °C for 2 h whereupon the cooling bath was
removed and sat. aq NH4Cl (5 mL) was added. The organic layer
was separated and the aqueous layer extracted with Et2O (3 × 20
mL). The combined organic layers were dried (Na2SO4) and con-
centrated in vacuo. The residue was purified by column chromatog-
raphy (SiO2, hexanes–Et2O) to give diphenyl sulfoxide (0.59 g, 2.92
HRMS (ES+): m/z calcd for C39H54O4Sn [M+]: 729.2936; found:
729.2955.
Anal. Calcd for C39H54O4Sn: C, 66.39; H, 7.71. Found: C, 66.30; H,
7.75.
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2752
K. Jarowicki et al.
PAPER
1-Phenylsulfinyl Glycal (SS)-23 (Scheme 10)
OTBS
OTBS
TBSO
TBSO
H2O2 (3.5 equiv)
TBSO
H
O
(NH4)2MoO4 (0.065 equiv)
O
EtOH, r.t.
70% (88% brsm)
TBSO
S
Ph
SPh
43
O
(SS)-44
mp: 123–124 °C
X-ray (Figure 1)
OTBS
TBSO
LDA (2.5 equiv)
O
S
THF, –78 °C
98%
Ph
O
(SS)-23
mp 60–63 °C
Scheme 10 Synthesis of 1-phenylsulfinyl glycal (SS)-23
Figure 1 Molecular structure of (SS)-44
1-Deoxy-2,3,4-tris-O-(tert-butyldimethylsilyl)-1-[(SS)-phenyl-
sulfinyl]-b-D-xylopyranoside (SS)-44
cooled to –78 °C and a solution of sulfoxide (SS)-44 (4.52 g, 7.52
mmol) in THF (30 mL) was added and the mixture stirred at –78 °C
for 30 min. The cooling bath was removed and a sat. aq NaHCO3 (5
mL) was added and the mixture allowed to warm to r.t. The product
was extracted with Et2O (3 × 20 mL) and the combined organic ex-
tracts were dried over Na2SO4, filtered and concentrated in vacuo.
The residue was purified by column chromatography (SiO2, hex-
anes–Et2O, gradient: 20:1 to 2:1, 0.5% Et3N) to give the 1-phenyl-
sulfinyl glycal (SS)-23 (3.47 g, 7.40 mmol, 98%) as a colourless oil
which crystallised on standing; mp 60–63 °C.
(NH4)2MoO4 (0.25 g, 1.3 mmol, 6.5 mol%) was added to H2O2 (7.2
mL, 30%, 70 mmol, 3.5 equiv.) at 0 °C. The resulting yellow solu-
tion was then added to a solution of the thioether 4321 (11.65 g, 20.0
mmol) in EtOH (160 mL). The reaction was allowed to warm grad-
ually to r.t. over 18 h. A portion of H2O (50 mL) was added and the
mixture was concentrated in vacuo. The resulting solution was ex-
tracted with CH2Cl2 (3 × 50 mL). The combined CH2Cl2 extracts
were dried over Na2SO4 and concentrated in vacuo. The residue was
purified by column chromatography (SiO2, hexanes–Et2O, gradient:
20:1 to 10:1) to give recovered thioether 43 (2.09 g, 3.6 mmol, 18%)
and sulfoxide (SS)-44 (8.24 g, 14.0 mmol, 70% or 88% based on re-
covered starting material) as a colourless crystalline solid; mp 123–
124 °C (hexane).
[a]D29 –2.5 (c 1.05, CHCl3).
IR (film): 2953m, 2928s, 2856m, 1648m, 1255m cm–1.
1H NMR (500 MHz, CDCl3): d = 7.73–7.70 (2 ArH, m), 7.50–7.43
(3 ArH, m), 5.74 (1 H, dd, J = 5.0, 1.4 Hz, C2H), 4.03 (1 H, dd, J =
11.0, 1.4 Hz, C5HAHB), 3.95 (1 H, ddd, J = 5.0, 3.0, 1.4 Hz, C3H),
3.90 (1 H, ddd, J = 11.0, 3.3, 1.4 Hz, C5HAHB), 3.66 (1 H, tt, J =
3.1, 1.4 Hz, C4H), 0.90 [9 H, s, (CH3)3C], 0.72 [9 H, s, (CH3)3C],
0.13 (3 H, s, CH3Si), 0.11 (3 H, s, CH3Si), 0.00 (3 H, s, CH3Si),
–0.08 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 157.5 (C1), 142.3 (CAr), 131.9
(CArH), 129.4 (2 CArH), 126.4 (2 CArH), 101.3 (C2H), 69.5 (C4H),
69.0 (C5H2), 65.5 (C3H), 26.1 [(CH3)3C], 25.8 [(CH3)3C], 18.3
[C(CH3)3], 18.0 [C(CH3)3], –4.0 (CH3Si), –4.4 (CH3Si), –4.5
(CH3Si), –4.7 (CH3Si).
[a]D29 +32.6 (c 1, CHCl3).
IR (diamond compression system): 2953m, 2929m, 2857m, 1256m
cm–1.
1H NMR (500 NMR, CDCl3): d = 7.68–7.64 (2 ArH, m), 7.52–7.44
(3 ArH, m), 4.44 (1 H, br d, J = 2.1 Hz, C2H), 4.24 (1 H, dd, J =
12.2, 2.6 Hz, C5HAHB), 4.24 (1 H, br s, C1H), 3.86 (1 H, s with fine
splitting, C3H), 3.69–3.64 (2 H, m, C4H + C5HAHB), 0.98 [9 H, s,
(CH3)3C], 0.892 [9 H, s, (CH3)3C], 0.890 [9 H, s, (CH3)3C], 0.23 (3
H, s, CH3Si), 0.15 (3 H, s, CH3Si), 0.14 (3 H, s, CH3Si), 0.11 (3 H,
s, CH3Si), 0.08 (3 H, s, CH3Si), 0.07 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 145.2 (CAr), 131.1 (CArH), 129.2
(2 CArH), 124.9 (2 CArH), 98.1 (C1H), 71.1 (C3H), 69.3 (C4H), 66.7
(C2H), 65.4 (C5H2), 26.3 [2(CH3)3C], 26.1 [(CH3)3C], 18.6
[C(CH3)3], 18.5 [C(CH3)3], 18.3 [C(CH3)3], –4.15 (CH3Si), –4.21
(CH3Si), –4.3 (CH3Si), –4.38 (CH3Si), –4.42 (CH3Si), –4.6
(CH3Si).
HRMS (ES+): m/z calcd for C23H40O4Si2SNa (M + Na)+: 491.2084;
found: 491.2103.
1-Phenylsulfinyl Glycal (RS)-36 (Scheme 11)
4,6-O-Benzylidene-2,3-di-O-tert-butyldimethylsilyl-1-[(RS)-phe-
nylsulfinyl]-a-D-glucopyranoside [(RS)-46] and its Epimer (SS)-
46; Typical Procedure 4
LRMS (ES+): m/z (%) = 623.4 (M + Na)+, (100).
Anal. Calcd for C29H56O5Si3S: C, 57.95; H, 9.39. Found: C, 57.75;
H, 9.55.
To a suspension of the thioether 4528 (10.7 g, 18.3 mmol) and
NaHCO3 (18.4 g, 220 mmol) in CH2Cl2 (400 mL) at –78 °C was
added dropwise a solution of mCPBA (3.8 g, 70%, 20.1 mmol) in
CH2Cl2 (100 mL) and the mixture was stirred at –78 °C for 4 h. The
cooling bath was removed and sat. aq solutions of Na2S2O3 (100
mL) and NaHCO3 (100 mL) were added sequentially in one portion
with vigorous stirring. When the mixture reached r.t., the phases
were separated and the aqueous phase was extracted with CH2Cl2 (3
× 50 mL). The combined organic extracts were dried (Na2SO4) and
concentrated in vacuo. 1H NMR spectroscopic analysis of the crude
The structure and stereochemistry of (SS)-44 was established by X-
ray crystallography (Figure 1).
1,2-Dideoxy-3,4-bis(tert-butyldimethylsilyl)-1-[(SS)-phenylsulfi-
nyl]-D-threo-pent-1-enopyranose [(SS)-23]; Typical Procedure 3
To a solution of i-Pr2NH (2.91 g, 4.0 mL, 28.8 mmol, 3.8 equiv) in
THF (13 mL) was added n-BuLi (2.36 M in pentane, 8.1 mL, 19.2
mmol, 2.5 equiv) at a rate sufficient to maintain the internal temper-
ature at –30 °C. After stirring for 15 min, the reaction mixture was
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2753
(SS)-46 (Minor Epimer)
Ph
O
Colourless oil; [a]D24 +0.2 (c 1.00, CHCl3).
O
O
IR (film): 3034m, 2927s, 2857s, 1471m, 1375s, 1249m, 1082s,
1039s, 1006s cm–1.
TBSO
TBSO
1H NMR (500 MHz, CDCl3): d = 7.72–7.68 (2 ArH, m), 7.54–7.52
(3 ArH, m), 7.51–7.49 (2 ArH, m), 7.41–7.37 (3 ArH, m), 5.57 (1
H, s, CHPh), 4.54 (1 H, t, J = 1.3 Hz, C2H), 4.30 (1 H, dt, J = 10.3,
5.1 Hz, C6HAHB), 4.28 (1 H, t, J = 1.7 Hz, C1H), 4.12 (1 H, dt, J =
10.3, 5.1 Hz, C5H), 3.99 (1 H, dt, J = 5.6, 1.3 Hz, C3H), 3.95 (1 H,
dd, J = 10.3, 5.6 Hz, C4H), 3.58 (1 H, t, J = 10.3 Hz, C6HAHB), 1.57
[9 H, s, (CH3)3C], 0.89 [9 H, s, (CH3)3C], 0.172 (3 H, s, CH3Si),
0.170 (3 H, s, CH3Si), 0.16 (3 H, s, CH3Si), 0.13 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 143.1 (CAr), 137.5 (CAr), 131.7
(CArH), 129.3 (CArH), 129.2 (2 CArH), 128.6 (2 CArH), 126.3 (2
CArH), 125.7 (2 CArH), 101.7 (CHPh), 96.7 (C1H), 84.4 (C4H), 75.5
(C3H), 73.3 (C2H), 70.0 (C6H2), 64.0 (C5H), 26.01 [(CH3)3C],
25.98 [(CH3)3C], 18.3 [C(CH3)], 18.2 [C(CH3)], –3.9 (CH3Si),
–4.30 (CH3Si), –4.33 (CH3Si), –4.8 (CH3Si).
SPh
45
mCPBA (1.1 equiv)
NaHCO3 (12 equiv)
CH2Cl2, –78 °C
Ph
Ph
93%
O
H
S
O
O
H
S
O
TBSO
TBSO
TBSO
+
2:1
O
O
O
O
TBSO
Ph
Ph
(SS)-46
(RS)-46
mp 120–121 °C
HRMS (ES+): m/z calcd for C31H49O6SSi2 (M + H)+: 605.2706;
found: 605.2766.
LDA (2.5 equiv)
THF, –78 °C
82%
LDA (2.5 equiv)
THF, –78 °C
88%
Anal. Calcd for C31H48O6SSi2: C, 61.55; H, 8.00. Found: C, 61.80;
H, 8.10.
Ph
O
Ph
O
S
O
O
1,5-Anhydro-2-deoxy-4,6-O-[(R)-phenylmethylene]-3-O-tert-
butyldimethylsilyl-1-[(RS)-phenylsulfinyl]-D-arabino-hex-1-
enitol [(RS)-36] and its Epimer (SS)-36
Treatment of sulfoxide (RS)-46 (9.85 g, 16.3 mmol) with LDA (2.4
equiv) according to typical procedure 3 gave 1-phenylsulfinyl gly-
cal (RS)-36 (6.78 g, 14.3 mmol, 88%) as a white solid; mp 118.5–
120.5 °C (hexanes–Et2O).
TBSO
TBSO
O
O
O
O
S
Ph
Ph
(RS)-36
mp 118.5–120.5 °C
X-ray (Figure 2)
(SS)-36
mp 125.5–126.0 °C
[a]D20 –137 (c 1.00, CHCl3).
IR (diamond compression system): 3061s, 2927s, 2856s, 1632s,
1473s, 1378s, 1170s, 977s, 700s cm–1.
Scheme 11 Synthesis of 1-phenylsulfinyl glycal (RS)-36
1H NMR (500 MHz, CDCl3): d = 7.71–7.69 (2 ArH, m), 7.53–7.52
(3 ArH, m), 7.45–7.44 (2 ArH, m) 7.36–7.35 (3 ArH, m), 5.62 (1 H,
d, J = 2.1 Hz, C2H), 5.51 (1 H, s, CHPh), 4.62 (1 H, dd, J = 7.3, 2.1
Hz, C3H), 4.29 (1 H, dd, J = 10.3, 5.1 Hz, C6HAHB), 3.99 (1 H, dt,
J = 10.3, 5.6 Hz, C5H), 3.75 (1 H, dd, J = 10.3, 7.7 Hz, C4H), 3.71
(1 H, t, J = 10.3 Hz, C6HAHB), 0.89 [9 H, s, (CH3)3C], 0.11 (3 H, s,
CH3Si), 0.08 (3 H, s, CH3Si).
product revealed two epimeric sulfoxides (2:1) according to inte-
gration of the signals for the benzylidene acetal proton at d = 5.44
for (RS)-46 and d = 5.57 for (SS)-46. The mixture was separated by
column chromatography (SiO2, hexanes–Et2O, 20:1, 10:1, 5:1, 2:1)
to give (SS)-46 (3.86 g, 6.4 mmol, 35%) and (RS)-46 (6.43 g, 10.6
mmol, 58%).
13C NMR (75 MHz, CDCl3): d = 155.9 (C1), 141.6 (CAr), 137.2
(CAr), 132.0 (CArH), 129.5 (2 CArH), 129.3 (CArH), 128.5 (2 CArH),
126.2 (2 CArH), 125.7 (2 CArH), 107.1 (C2H), 101.7 (CHPh), 80.2
(C4H), 71.9 (C5H), 68.0 (C6H2), 67.9 (C3H), 26.0 [(CH3)2C], 18.5
[C(CH3)], –4.2 (CH3Si), –4.5 (CH3Si).
HRMS (ES+): m/z calcd for C25H33O5SSi (M + H)+: 473.1818;
found: 473.1797.
(RS)-46 (Major Epimer)
White solid; mp 120–121 °C (hexanes); [a]D –117 (c 1.00,
CHCl3).
24
IR (diamond compression system): 2928s, 1582w, 1473s, 1254s,
975s, 933s, 748s, 692s, 564s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.69–7.68 (2 ArH, m), 7.53–7.50
(3 ArH, m), 7.44–7.42 (2 ArH, m), 7.36–7.34 (3 ArH, m), 5.44 (1
H, s, CHPh), 4.18 (1 H, dd, J = 10.7, 5.1 Hz, C6HAHB), 4.07 (1 H,
d, J = 6.0 Hz, C1H), 3.98 (1 H, t, J = 5.1 Hz, C2H), 3.89 (1 H, dd,
J = 8.1, 5.1 Hz, C3H), 3.79 (1 H, t, J = 10.3 Hz, C6HAHB), 3.76 (1
H, dd, J = 9.8, 8.1 Hz, C4H), 3.65 (1 H, dt, J = 9.8, 5.1 Hz, C5H),
0.90 [9 H, s, (CH3)3C], 0.85 [9 H, s, (CH3)3C], 0.10 (3 H, s, CH3Si),
0.06 (3 H, s, CH3Si), 0.042 (3 H, s, CH3Si), 0.037 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 141.5 (CAr), 137.3 (CAr), 131.7
(CArH), 129.5 (CArH), 129.3 (2 CArH), 128.5 (2 CArH), 126.8 (2
CArH), 125.7 (2 CArH), 102.5 (CHPh), 97.5 (C1H), 81.8 (C4H), 77.2
(C3H), 72.5 (C2H), 69.1 (C6H2), 68.4 (C5H), 26.6 [(CH3)3C], 26.3
[(CH3)3C], 18.8 [C(CH3)], 18.5 [C(CH3)], –2.7 (CH3Si), –3.1
(CH3Si), –3.2 (CH3Si), –4.2 (CH3Si).
Anal. Calcd for C25H32O5SSi: C, 63.53; H, 6.82. Found: C, 63.80;
H, 7.05.
(SS)-36
An analogous procedure was used to obtain (SS)-36 in 82–84% yield
from sulfoxide (SS)-46. (SS)-36 was obtained as a white solid; mp
125.5–126.0 °C (hexanes–Et2O).
[a]D25 +6 (c 1.00, CHCl3).
IR (diamond compression system): 3065m, 2926s, 2854s, 1639s,
1376s, 1258s, 1085s, 837s, 746s, 692s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.73–7.67 (2 ArH, m), 7.54–7.49
(3 ArH, m), 7.46–7.42 (2 ArH, m) 7.37–7.33 (3 ArH, m), 5.63 (1 H,
d, J = 2.3 Hz, C2H), 5.54 (1 H, s, CHPh), 4.59 (1 H, dd, J = 7.4, 2.3
Hz, C3H), 4.30 (1 H, dd, J = 10.5, 5.1 Hz, C6HAHB), 3.86 (1 H, dt,
J = 10.1, 5.0 Hz, C5H), 3.78 (1 H, dd, J = 10.0, 7.3 Hz, C4H), 3.75
HRMS (ES+): m/z calcd for C31H49O6SSi2 (M + H)+: 605.2788.;
found: 605.2770.
Anal. Calcd for C31H48O6SSi2: C, 61.55; S, 5.30; H, 8.00. Found: C,
61.5; H, 8.05.
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2754
K. Jarowicki et al.
PAPER
(1 H, t, J = 10.3 Hz, C6HAHB), 0.90 [9 H, s, (CH3)3C], 0.12 (3 H, s,
CH3Si), 0.09 (3 H, s, CH3Si).
O
O
13C NMR (75 MHz, CDCl3): d = 156.2 (C1), 141.7 (CAr), 137.0
(CAr), 131.7 (CArH), 129.3 (2 CArH), 129.2 (CArH), 128.3 (2 CArH),
126.1 (2 CArH), 125.1 (2 CArH), 107.0 (C2H), 101.6 (CHPh), 80.0
(C4H), 71.1 (C5H), 67.9 (C6H2), 67.9 (C3H), 25.9 [(CH3)2C], 18.3
[C(CH3)], –4.3 (CH3Si), –4.7 (CH3Si).
O
O
O
SPh
47
HRMS (ES+): m/z calcd for C25H32O5SSiNa (M + Na)+: 495.1632;
found: 495.1636.
mCPBA (1.1 equiv)
94% NaHCO3 (12 equiv)
CH2Cl2, –78 °C
Anal. Calcd for C25H32O5SSi: C, 63.53; H, 6.82. Found: C, 63.50;
H, 6.85.
O
H
S
O
O
H
S
O
O
O
O
O
The structure and stereochemistry of (RS)-36 was established by X-
ray crystallography (Figure 2).
+
4.5:1
O
O
O
Ph
Ph
O
(RS)-48
mp 125.0–126.5 °C
X-ray (Figure 3)
(SS)-48
mp 164.5–166.5 °C
LDA (2.5 equiv)
THF, –78 °C
O
S
O
O
S
O
TBSCl (1.2 equiv)
HO
TBSO
imidazole (2.5 equiv)
O
O
O
O
DMF, r.t.
79% from (SS)-48
Ph
Ph
(SS)-49
mp 144.5–146.0 °C
(SS)-25
Scheme 12 Synthesis of 1-phenylsulfinyl glycal (SS)-25
(3 H, s, CH3), 1.45 (3 H, s, CH3), 1.40 (3 H, s, CH3), 1.19 (3 H, s,
CH3).
13C NMR (75 MHz, CDCl3): d = 139.1 (CAr), 132.0 (CArH), 128.8
(2 CArH), 126.7 (2 CArH), 112.2 [C(CH3)2], 98.7 [C(CH3)2], 92.7
(C1H), 79.7 (C3H), 70.7 (C5H), 69.9 (C2H), 66.4 (C4H), 62.8
(C6H2), 28.7 (CH3C), 26.9 (CH3C), 26.7 (CH3C), 18.9 (CH3C).
Figure 2 Molecular structure of (RS)-36
1-Phenylsulfinyl Glycal (SS)-25 (Scheme 12)
1-Deoxy-2,3:4,6-di-O-isopropylidene-1-[(SS)-phenylsulfinyl]-b-
D-galactopyranoside [(SS)-48] and its Epimer (RS)-48
Anal. Calcd for C18H24O6S: C, 58.68; H, 6.57. Found: C, 58.6; H,
6.75.
Oxidation of thioether 4741 (7.08 g, 20.0 mmol) according to typical
procedure 4 gave a mixture of two diastereoisomeric sulfoxides
(SS)-48 and (RS)-48 in the ratio 4.5:1 according to integration of the
1H NMR signals for C1H at d = 4.53 for (SS)-48 and d = 4.42 for
(RS)-48. The products were separated by column chromatography
(SiO2, hexanes–EtOAc with 0.5% of Et3N) to give the less polar
minor sulfoxide (RS)-48 (1.04 g, 2.8 mmol, 14%) followed by a
3.9:1 mixture of (SS)-48 and (RS)-48 (1.03 g, 2.8 mmol, 14%), and
finally the more polar major sulfoxide (SS)-48 (4.84 g, 13.1 mmol,
66%). The total yield of both epimers was 94%.
(RS)-48 (Minor Epimer)
White solid; mp 125.0–126.5 °C (hexane–EtOAc).
[a]D31 –92 (c 1.36, CHCl3).
IR (diamond compression system): 2990m, 2934m, 1443m, 1382m,
1279m, 1243s, 1224s, 1150s, 1072s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.74–7.71 (2 ArH, m), 7.50–7.47
(3 ArH, m), 4.42 (1 H, d, J = 9.4 Hz, C1H), 4.38 (1 H, dd, J = 2.8,
1.5 Hz, C4H), 4.01 (1 H, dd, J = 13.1, 2.2 Hz, C6HAHB), 3.90 (1 H,
dd, J = 13.1, 1.5 Hz, C6HAHB), 3.78 (1 H, t, J = 9.4 Hz, C2H), 3.55
(1 H, dd, J = 9.3, 2.7 Hz, C3H), 3.34 (1 H, q, J = 1.7 Hz, C5H), 1.39
(3 H, s, CH3), 1.38 (3 H, s, CH3), 1.31 (3 H, s, CH3), 1.29 (3 H, s,
CH3).
13C NMR (75 MHz, CDCl3): d = 139.0 (CAr), 131.8 (CArH), 128.9
(2 CArH), 126.2 (2 CArH), 112.0 [C(CH3)2], 98.8 [C(CH3)2], 92.2
(C1H), 79.4 (C3H), 70.7 (C5H), 68.4 (C2H), 66.4 (C4H), 62.8
(C6H2), 29.0 (CH3C), 26.8 (CH3C), 26.4 (CH3C), 18.8 (CH3C).
(SS)-48 (Major Epimer)
White solid; mp 164.5–166.5 °C (hexane–EtOAc).
[a]D21 +5 (c 1.00, CHCl3).
IR (diamond compression system): 3063m, 2989s, 2923s, 1478s,
1441s, 1381s, 1322m, 1308m, 1212s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.79–7.76 (2 ArH, m), 7.54–7.50
(3 ArH, m), 4.53 (1 H, d, J = 9.6 Hz, C1H), 4.39 (1 H, dd, J = 2.6,
1.5 Hz, C4H), 4.02 (1 H, dd, J = 13.1, 2.2 Hz, C6HAHB), 3.95 (1 H,
dd, J = 13.1, 1.3 Hz, C6HAHB), 3.84 (1 H, t, J = 9.4 Hz, C2H), 3.59
(1 H, dd, J = 9.2, 2.6 Hz, C3H), 3.32 (1 H, q, J = 1.7 Hz, C5H), 1.46
The structure and stereochemistry of (RS)-48 was established by X-
ray crystallography (Figure 3).
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2755
column chromatography (SiO2, hexanes–Et2O) to give the TBS-
protected 1-phenylsulfinyl glycal (SS)-25 (1.15 g, 2.7 mmol, 79%)
as a colourless, viscous oil.
[a]D26 –10 (c 1.00, CHCl3).
IR (diamond compression system): 3061m, 2992s, 2929s, 2894s,
2857s, 1655s, 1473s, 1463s, 1444s, 1382s, 1361m, 1342m, 1311m,
1261s, 1183s, 1131s, 1090s, 1051s, 1023m, 1006m, 961s, 929s,
881s, 837s, 803s, 778s, 749s, 688s, 666m, 596m, 562m, 538m,
516m, 480m cm–1.
1H NMR (500 MHz, CDCl3): d = 7.74–7.70 (2 ArH, m), 7.49–7.43
(3 ArH, m), 5.57 (1 H, t, J = 1.7 Hz, C2H), 4.65 (1 H, dd, J = 4.5,
2.1 Hz, C3H), 4.05 (1 H, ill-resolved ddd, J = 4.5, 1.5, 1.3 Hz, C4H),
3.94 (1 H, dd, J = 12.9, 1.7 Hz, C6HAHB), 3.87 (1 H, dd, J = 12.9,
1.9 Hz, C6HAHB), 3.80–3.82 (1 H, m, C5H), 1.40 (3 H, s, CH3), 1.25
(3 H, s, CH3), 0.89 [9 H, s, (CH3)3C], 0.09 (3 H, s, CH3Si), 0.09 (3
H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 155.0 (C1), 142.1 (CAr), 131.4
(CArH), 129.2 (2 CArH), 125.5 (2 CArH), 105.6 (C2H), 99.3
[C(CH3)2], 71.4 (C5H), 66.1 (C3H), 65.7 (C4H), 62.8 (C6H), 29.3
(CH3C), 26.1 [(CH3)3C]), 18.8 (CH3C), 18.6 [(CH3)3C], –4.0
(CH3Si), –4.1 (CH3Si).
HRMS (ES+): m/z calcd for C21H32O5SNa (M + Na)+: 447.1632;
found: 447.1614.
1-Phenylsulfinyl Glycal (RS)-26 (Scheme 13)
OH
OAc
1. PhSH (1.2 equiv)
BF3⋅OEt2 (0.5 equiv)
CH2Cl2, 0 °C to r.t.
Figure 3 Molecular structure of (RS)-48
HO
HO
AcO
AcO
O
O
2. NaOMe (0.09 equiv)
MeOH, r.t.
1,5-Anhydro-4,6-O-isopropylidene-1-[(SS)-phenylsulfinyl]-D-
lyxo-hex-1-enitol [(SS)-49]
69%
SPh
OAc
Treatment of sulfoxide (SS)-48 (1.84 g, 5.0 mmol) with LDA (2.0
equiv) according to typcical procedure 3 gave the 1-phenylsulfinyl
glycal (SS)-49 (1.22 g) as a pale yellow solid. The crude product was
used in the next step without further purification. An analytical sam-
ple was obtained by recrystallisation from EtOAc; mp 144.5–
146.0 °C.
50
51
1. TBSCl (3.6 equiv), imidazole (7.75 equiv)
DMF, r.t., 5 d
66%
2. TBSOTf (1.4 equiv), DIPEA (2.3 equiv)
CH2Cl2, r.t., 2 d
OTBS
OTBS
O
[a]D21 –23 (c 1.00, CHCl3).
TBSO
TBSO
H2O2 (10 equiv)
TBSO
H
O
(NH4)2MoO4 (0.06 equiv)
IR (diamond compression system): 3500s, 3066m, 2997s, 2938s,
2868m, 1693s, 1478m, 1447m, 1412s, 1381s, 1354m, 1267m,
1236s, 1176s, 1145m, 1112s, 1083s, 1038s, 997m, 959m, 922m,
851m, 813m cm–1.
EtOH, r.t.
70% (76% brsm)
TBSO
S
Ph
O
SPh
1H NMR (500 MHz, CDCl3): d = 7.71–7.67 (2 ArH, m), 7.47–7.43
(3 ArH, m), 5.61 (1 H, t, J = 1.7 Hz, C2H), 4.46 (1 H, ddd, J = 10.8,
4.7, 1.6 Hz, C3H), 4.14 (1 H, poorly resolved ddd, J = 4.9, 1.5, 1.3
Hz, C4H), 3.94 (1 H, dd, J = 13.0, 1.6 Hz, C6HAHB), 3.89 (1 H, dd,
J = 13.0, 1.9 Hz, C6HAHB), 3.82 (1 H, q, J = 1.7 Hz, C5H), 2.74 (1
H, d, J = 11.1 Hz, OH), 1.41 (3 H, s, CH3), 1.19 (3 H, s, CH3).
13C NMR (75 MHz, CDCl3): d = 155.41 (C1), 141.55 (CAr), 131.08
(CArH), 128.85 (2 CArH), 124.89 (2 CArH), 104.09 (C2H), 99.16
[C(CH3)2], 70.60 (C5H), 64.33 (C4H), 63.52 (C3H), 62.09 (C6H),
28.76 (CH3C), 18.47 (CH3C).
(RS)-53
52
LDA (2.5 equiv)
THF, –78 °C
66%
(87% brsm)
OTBS
OTBS
OTBS
O
TBSO
TBSO
HO
O
O
O
O
Li
TBS
S
S
S
Ph
Ph
Ph
O
Anal. Calcd for C15H18O5S: C, 58.05; H, 5.85. Found: C, 57.85; H,
5.95.
(RS)-26
mp 51–54 °C
(RS)-55 (7%)
mp 77.0–79.0 °C
X-ray (Figure 4)
(RS)-54
1,5-Anhydro-3-O-tert-butyldimethylsilyl-4,6-O-isopropylidene-
1-[(SS)-phenylsulfinyl]-D-lyxo-hex-1-enitol [(SS)-25]
Scheme 13 Synthesis of 1-Phenylsulfinyl Glycal (RS)-26
1-Phenylsulfinyl glycal (SS)-49 (1.05 g, 3.4 mmol), TBSCl (0.62 g,
4.08 mmol) and imidazole (0.58 g, 8.5 mmol) were dissolved in
DMF (23 mL). After stirring at r.t. for 12 h, H2O (250 mL) was add-
ed. The phases were separated and the aqueous layer was extracted
with Et2O (3 × 50 mL). The combined organic extracts were dried
(Na2SO4) and concentrated in vacuo. The residue was purified by
Phenyl 1-Thio-a-D-arabinopyranoside (51)
Thiophenol (8.7 mL, 84.3 mmol) and then BF3·OEt2 (4.5 mL, 35.1
mmol) were added to a solution of tetra-O-acetyl-a-D-arabinopyra-
nose 5042 (22.35 g, 70.2 mmol) in CH2Cl2 (75 mL) at 0 °C. After 2.5
h at r.t., the reaction mixture was diluted with CH2Cl2 (75 mL) and
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2756
K. Jarowicki et al.
PAPER
the mixture washed with sat. aq NaHCO3 (2 × 150 mL), sat. aq.
NaOH (2 × 50 mL) and H2O (2 × 150 mL). The organic layer was
dried (Na2SO4) and concentrated in vacuo. The residue was dis-
solved in MeOH (60 mL) and a solution of NaOMe in MeOH (0.1
M, 60 mL, 6 mmol) was added. The mixture was stirred for 1 h at
r.t., then neutralised by stirring for 30 min with Amberlite IR-120
(10 g). The suspension was filtered and the filtrate concentrated in
vacuo. The residue was purified by column chromatography (SiO2,
hexanes–EtOAc gradient, 2:1 to 1:3) to give the title triol 51 (11.8
g, 48.6 mmol, 69%, 2 steps) as a colourless foam: mp 89–92 °C.
[a]D21 +10.2 (c 0.41, CHCl3) {Lit.43 (for L-enantiomer) [a]D23 –12.6
(c 0.4, CHCl3)}. The 1H NMR spectrum of triol 51 recorded at 500
MHz was consistent with the data reported in the literature.43
1H NMR (500 MHz, CDCl3): d = 7.68–7.64 (2 ArH, m), 7.52–7.46
(3 ArH, m), 4.54 (1 H, d, J = 3.6 Hz, C2H), 4.18 (1 H, ddd, J = 10.6,
4.6, 2.2 Hz, C4H), 4.05 (1 H, t, J = 10.4 Hz, C5HAHB), 3.98–3.94 (2
H, m, C1H and C3H), 3.50 (1 H, ddd, J = 10.0, 4.7, 0.6 Hz,
C5HAHB), 1.00 [9 H, s, (CH3)3C], 0.91 [9 H, s, (CH3)3C], 0.87 [9 H,
s, (CH3)3C], 0.23 (3 H, s, CH3Si), 0.17 (3 H, s, CH3Si), 0.14 (3 H, s,
CH3Si), 0.10 (3 H, s, CH3Si), 0.09 (3 H, s, CH3Si), 0.08 (3 H, s,
CH3Si).
13C NMR (75 MHz, CDCl3): d = 145.2 (CAr), 131.2 (CArH), 129.2
(2 CArH), 124.9 (2 CArH), 97.1 (C1H), 73.0 (C3H), 69.1 (C4H), 65.6
(C2H), 63.7 (C5H2), 26.4 [(CH3)3C], 26.2 [(CH3)3C], 26.0
[(CH3)3C], 18.7 [C(CH3)3], 18.7 [C(CH3)3], 18.2 [C(CH3)3], –4.2 (2
CH3Si), –4.3 (CH3Si), –4.6 (2 CH3Si), –4.7 (CH3Si).
HRMS (ES+): m/z calcd for C29H57O5Si3S (M + H)+: 601.3239;
found: 601.3235.
Phenyl 2,3,4-Tri-O-tert-butyldimethylsilyl-1-thio-a-D-arabino-
pyranoside (52)
Imidazole (10.2 g, 0.155 mol) and TBSCl (10.85 g, 72 mmol) were
added to a solution of the triol 51 (4.85 g, 20.0 mmol) in DMF (50
mL) at r.t. After stirring for 5 d, the reaction mixture was poured
into H2O (300 mL) and the aqueous phase extracted with Et2O (3 ×
250 mL). The combined organic extracts were dried (Na2SO4) and
concentrated in vacuo. The residue was purified by column chroma-
tography (SiO2, petroleum ether–Et2O, 20:1) to yield a mixture of
di- and tri-protected compound (6.06 g). The mixture was dissolved
in CH2Cl2 (30 mL). DIPEA (8.0 mL, 46.0 mmol) was added, fol-
lowed by the dropwise addition of TBSOTf (6.4 mL, 28 mmol). Af-
ter 2 d at r.t., the mixture was washed with aq 5% HCl (2 × 55 mL)
and H2O (2 × 55 mL), and the aqueous layers were combined and
extracted with CH2Cl2 (3 × 35 mL). The combined organic extracts
were dried (Na2SO4) and concentrated in vacuo. The residue was
purified by column chromatography (SiO2, hexanes–Et2O) to give
the title compound 52 (7.71 g, 13.2 mmol, 66%, 2 steps) as a colour-
less oil.
1,5-Anhydro-2-deoxy-3,4-di-O-tert-butyldimethylsilyl-1-[(RS)-
phenylsulfinyl]-D-erythro-pent-1-enitol [(RS)-26]
Reaction of sulfoxide (RS)-53 (5.17 g, 8.9 mmol) with LDA (2.5
equiv) according to typical procedure 3 gave a crude product that
was purified by column chromatography (SiO2, hexanes–Et2O) to
give the recovered starting material (RS)-53 (1.10 g, 1.83 mmol,
21%) followed by the 1-phenylsulfinyl glycal (RS)-26 (2.745 g, 5.8
mmol, 66% or 87% based on recovered starting material) as a co-
lourless oil which solidified on standing; mp 51–54 °C.
[a]D21 +110 (c 1.1, CHCl3).
IR (diamond compression system): 3057s, 2929s, 2857s, 1645s,
1471s, 1253s cm–1.
1H NMR (500 MHz, CHCl3): d = 7.68–7.63 (2 ArH, m), 7.50–7.46
(3 ArH, m), 7.26 (1 H, s), 5.65 (1 H, d, J = 4.9 Hz, C2H), 4.26–4.22
(1 H, m, C3H), 3.94 (1 H, t with fine splitting, J = 9.8 Hz, C5HAHB),
3.87–3.80 (2 H, m, C4H and C5HAHB), 0.89 [9 H, s, (CH3)3C], 0.82
[9 H, s, (CH3)3C], 0.11 (3 H, s, CH3Si), 0.09 (3 H, s, CH3Si), 0.04
(3 H, s, CH3Si), 0.00 (3 H, s, CH3Si).
[a]D21 +104.0 (c 0.54, CHCl3).
IR (film): 2953s, 2930s, 2858s, 1256s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.46 (2 ArH, d with fine splitting,
J = 7.0 Hz), 7.26 (2 ArH, t with fine splitting, J = 7.5, 2 Hz), 7.19 (1
ArH, tt, J = 7.3, 1.2 Hz), 5.12 (1 H, br s, C1H), 4.29 (1 H, t, J = 10.7
Hz, C5HAHB), 4.15 (1 H, ddd, J = 10.6, 4.5, 2.5 Hz, C4H), 4.04 (1
H, d, J = 3.7 Hz, C2H), 3.81 (1 H, t, J = 3.0 Hz, C3H), 3.39 (1 H,
dd, J = 10.4, 4.6 Hz, C5HAHB), 0.99 [9 H, s, (CH3)3C], 0.91 [9 H, s,
(CH3)3C], 0.89 [9 H, s, (CH3)3C], 0.15 (3 H, s, CH3Si), 0.13 (3 H, s,
CH3Si), 0.09 (9 H, s, 3 CH3Si), 0.07 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 156.8 (C1), 141.7 (CAr), 131.5
(CArH), 129.3 (2 CArH), 125.3 (2 CArH), 105.9 (C2H), 68.4 (C5H2),
67.7 (C4H), 64.6 (C3H), 26.1 [(CH3)3C], 26.1 [(CH3)3C], 18.5
[C(CH3)3], 18.4 [C(CH3)3], –4.0 (CH3Si), –4.1 (CH3Si), –4.2
(CH3Si), –4.6 (CH3Si).
HRMS (ES+): m/z calcd for C23H40O428Si232SNa (M + Na)+:
491.2078; found: 491.2084.
13C NMR (75MHz, CDCl3): d = 138.8 (CAr), 130.6 (2 CArH), 129.1
(2 CArH), 126.7 (CArH), 88.3 (C1H), 75.5 (C2H), 73.3 (C3H), 66.9
(C4H), 59.9 (C5H2), 26.5 [(CH3)3C], 26.4 [(CH3)3C], 26.1
[(CH3)3C], 18.8 [2 × C(CH3)3], 18.3 [C(CH3)3], –4.0 (CH3Si), –4.1
(CH3Si), –4.2 (CH3Si), –4.4 (2 CH3Si), –4.6 (CH3Si).
HRMS (ES+): m/z calcd for C29H56O4Si3SNa (M + Na)+: 607.3099;
found: 607.3079.
(RS)-55
The last component to elute was 1,5-anhydro-2-deoxy-3-tert-bu-
tyldimethylsilyl-4-O-tert-butyldimethylsilyl-1-[(RS)-phenylsulfi-
nyl]-D-erythro-pent-1-enitol [(RS)-55] (0.27 g, 0.58 mmol, 7%);
colourless solid; mp 77–79 °C (hexane).
[a]D25 +158 (c 1.52, CHCl3).
IR (diamond compression system): 3306brm, 2927m, 2159s, 2027s,
1972s, 1586m, 1471m cm–1.
1-Deoxy-2,3,4-tri-O-tert-butyldimethylsilyl-1-[(RS)-phenylsulfi-
nyl]-a-D-arabinopyranoside [(RS)-53]
1H NMR (500 MHz, CHCl3): d = 7.52–7.43 (2 ArH, m), 7.68–7.63
(3 ArH, m), 4.13 (1 H, dd, J = 3.5, 1.2 Hz, C3H), 3.98 (1 H, td, J =
9.8, 3.9 Hz, C4H), 3.94 (1 H, ddd, J = 10.1, 4.2, 1.2 Hz, C5HAHB),
3.76 (1 H, t, J = 10.0 Hz, C5HAHB), 2.54 (1 H, br s, OH), 1.03 [9 H,
s, (CH3)3C], 0.86 [9 H, s, (CH3)3C], 0.39 (3 H, s, CH3Si), 0.38 (3 H,
s, CH3Si), 0.08 (3 H, s, CH3Si), 0.03 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 161.5 (C1), 141.3 (CAr), 130.8
(CArH), 129.2 (2 CArH), 125.3 (2 CArH), 115.2 (C2), 66.6 (CH), 66.4
(CH), 66.1 (C5H2), 27.4 [(CH3)3C], 25.9 [(CH3)3C], 18.6 [(CCH3)3],
18.2 [CCH3)3], –1.0 (CH3Si), –4.0 (CH3Si), –4.5 (CH3Si), –4.7
(CH3Si).
Ammonium molybdate (26 mg, 0.132 mmol) was added to 30%
H2O2 (0.80 g, 22 mmol) at 0 °C. The resulting yellow solution was
then added to a solution of the thioether 52 (1.29 g, 2.20 mmol) in
EtOH (20 mL). The reaction was stirred at r.t. for 20 h. H2O (25 mL)
was added and the resulting solution extracted with CH2Cl2 (3 × 25
mL). The combined organic extracts were dried (Na2SO4) and con-
centrated in vacuo. The residue was purified by column chromatog-
raphy (SiO2, hexanes–Et2O) to give recovered thioether (80 mg,
0.13 mmol, 6%) and the title sulfoxide (RS)-53 (0.94 g, 1.56 mmol,
70% or 76% based on recovered thioether 52) as a colourless oil.
[a]D24 –12.1 (c 0.70, CHCl3).
IR (film): 2954m, 2930m, 2858m cm–1.
HRMS (ES+): m/z calcd for C23H40O428Si232SNa (M + Na)+:
491.2078; found: 491.2078.
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2757
The structure and stereochemistry of (RS)-55 was established by X-
ray crystallography (Figure 4).
1,6-Dideoxy-2,3-O-isopropylidene-4-O-tert-butyldimethylsilyl-
1-[(SS)-phenylsulfinyl]-a-L-mannopyranose [(SS)-57] and its
Epimer (RS)-57
Oxidation of the thioether 5628 (1.64 g, 4.0 mmol) with mCPBA
(1.08 g, 77%, 4.8 mmol) and NaHCO3 (4.0 g, 48 mmol) in CH2Cl2
(70 mL) at –78 °C for 2 h according to typical procedure 4 gave a
mixture of two diastereoisomeric sulfoxides (SS)-57 (less polar, ma-
jor) and (RS)-57 (more polar, minor) in a ratio of 12:1 as determined
by integration of the 1H NMR signal for C3H at 4.19 ppm for (SS)-
57 and 4.23 ppm for (RS)-57. The crude mixture was separated by
column chromatography (SiO2, hexanes–Et2O) to give first the less
polar major sulfoxide (SS)-57 (1.20 g, 2.8 mmol, 70%), then a mix-
ture of (SS)-57 and (RS)-57 (1:1.3, 0.159 g, 0.37 mmol, 9%) and fi-
nally the pure minor sulfoxide (RS)-57 (0.023 g, 0.053 mmol, 1%).
(SS)-57 (Major Epimer)
Mp 73–74 °C (MeOH–H2O); [a]D21 +55 (c 1.00, CHCl3).
IR (film): 3055s, 2931s, 2857s, 1473s, 1380s, 1250s, 1216s, 836s,
776s cm–1.
1H NMR (500 MHz, CHCl3): d = 7.68–7.63 (2 ArH, m), 7.58–7.51
(3 ArH, m), 4.75 (1 H, s, C1H), 4.74 (1 H, d, J = 5.8 Hz, C2H), 4.19
(1 H, dd, J = 7.2, 6.1 Hz, C3H), 3.84 (1 H, dq, J = 9.6, 6.2 Hz, C5H),
3.38 (1 H, dd, J = 9.4, 7.3 Hz, C4H), 1.49 (3 H, s, CH3C), 1.34 (3 H,
s, CH3C), 1.25 (3 H, d, J = 6.2 Hz, CH3CH), 0.91 [9 H, s, (CH3)3C],
0.17 (3 H, s, CH3Si), 0.10 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 142.1 (CAr), 131.9 (CArH), 129.6
(2 CArH), 124.9 (2 CArH), 109.2 [C(CH3)2], 96.5 (C1H), 79.0 (C3H),
75.4 (C4H), 73.4 (C5H), 71.4 (C2H), 28.4 (CH3C), 26.6 (CH3C),
26.2 [(CH3)3C], 18.5 [C(CH3)3], 18.2 (CH3CH), –3.6 (CH3Si), –4.6
(CH3Si).
Figure 4 Molecular structure of (RS)-55
When the elimination reaction was carried out according to typical
procedure 3 starting from the sulfoxide (RS)-53 (0.97 g, 1.6 mmol)
and LDA (2.5 equiv), but for 4 h at –78 °C instead of 1 h, the 1-phe-
nylsulfinyl glycal (RS)-26 (0.30 g, 0.64 mmol) was obtained in 40%
yield along with sulfoxide (RS)-55 (0.29 g, 0.61 mmol) in 38%
yield.
HRMS (ES+): m/z calcd for C21H34O5NaSSi (M + Na)+: 449.1794;
found: 449.1794.
1-Phenylsulfinyl Glycal (SS)-28 (Scheme 14)
OTBS
O
Anal. Calcd for C21H34O5SSi: C, 59.12; H, 8.03. Found: C, 59.0; H,
8.05.
O
O
(RS)-57 (Minor Epimer)
Colourless oil; [a]D26 –273 (c 0.88, CHCl3).
SPh
IR (film): 3060s, 2932s, 2857s, 1472s, 1381s, 1247s, 1219s, 837s,
778s cm–1.
56
1H NMR (500 MHz, CHCl3): d = 7.67 (2 ArH, dd, J = 7.9, 1.5 Hz),
7.60–7.51 (3 ArH, m), 4.71 (1 H, d, J = 1.7 Hz, C1H), 4.69 (1 H, dd,
J = 6.0, 1.7 Hz, C2H), 4.23 (1 H, dd, J = 6.8, 6.4 Hz, C3H), 4.09 (1
H, qd, J = 9.4, 6.3 Hz, C5H), 3.34 (1 H, dd, J = 9.4, 7.3 Hz, C4H),
1.50 (3 H, s, CH3C), 1.35 (3 H, s, CH3C), 1.06 (3 H, d, J = 6.0 Hz,
CH3CH), 0.88 [9 H, s, (CH3)3C], 0.13 (3 H, s, CH3Si), 0.06 (3 H, s,
CH3Si).
13C NMR (75 MHz, CDCl3): d = 140.4 (CAr), 131.8 (CArH), 129.6
(2 CArH), 125.5 (2 CArH), 109.5 [C(CH3)2], 93.3 (C1H), 79.6 (C3H),
75.4 (C4H), 73.7 (C5H), 73.3 (C2H), 28.3 (CH3C), 26.6 (CH3C),
26.2 [(CH3)3C], 18.5 [C(CH3)3], 18.1 (CH3C5H), –3.6 (CH3Si),
–4.6 (CH3Si).
mCPBA (1.2 equiv)
80% NaHCO3 (12 equiv)
CH2Cl2, –78 °C
OTBS
OTBS
O
O
O
O
+
12:1
H
O
H
O
S
S
Ph
O
Ph
O
(RS)-57
(SS)-57
mp 73.0–74.0 °C
LDA (2.5 equiv)
THF, –78 °C
79%
HRMS (ES+): m/z calcd for C21H35O5SSi (M + H)+: 427.1969;
found: 427.1968.
OTBS
OTBS
O
TBSOTf (1.2 equiv)
DIPEA (2.4 equiv)
HO
TBSO
1,5-Anhydro-2,6-dideoxy-4-O-tert-butyldimethylsilyl-1-[(SS)-
phenylsulfinyl]-l-arabino-hex-1-enitol [(SS)-58]
Reaction of sulfoxide (SS)-57 (1.71 g, 4.0 mmol) in THF (45 mL)
with LDA (2.5 equiv) in THF (14 mL) at –78 °C according to typ-
ical procedure 3 gave a solid residue. Recrystallisation from hex-
anes–Et2O gave the 1-phenylsulfinyl glycal (SS)-58 (1.17 g, 3.2
mmol, 79%) as a colourless solid; mp 131–132 °C.
O
O
CH2Cl2, r.t.
89%
S
S
Ph
Ph
O
(SS)-58
mp 131.0–132.0 °C
(SS)-28
mp 71.0–72.0 °C
X-ray (Figure 5)
[a]D28 +91 (c 1.00, CHCl3).
Scheme 14 Synthesis of 1-phenylsulfinyl glycal (SS)-28
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2758
K. Jarowicki et al.
PAPER
IR (film): 3429brs, 3059m, 2935s, 2855s, 1639s, 1444s, 1252s,
1111s, 844s cm–1.
1H NMR (500 MHz, CHCl3): d = 7.72–7.68 (2 ArH, m), 7.53–7.46
(3 ArH, m), 5.66 (1 H, d, J = 2.9 Hz, C2H), 4.25 (1 H, dt, J = 6.3,
2.9 Hz, C3H), 3.96 (1 H, qd, J = 8.6, 6.4 Hz, C5H), 3.41 (1 H, dd,
J = 8.7, 6.3 Hz, C4H), 1.86 (1 H, d, J = 6.3 Hz, OH), 1.22 (1 H, d,
J = 6.5 Hz, CH3CH), 0.87 [9 H, s, (CH3)3C], 0.12 (3 H, s, CH3Si),
0.06 (3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 156.3 (C1), 141.6 (CAr), 131.8
(CArH), 129.4 (2 CArH), 125.8 (2 CArH), 105.6 (C2H), 79.5 (C5H),
75.7 (C4H), 70.5 (C3H), 26.2 [(CH3)3C], 18.4 [C(CH3)3], 17.5
(CH3CH), –3.6 (CH3Si), –4.5 (CH3Si).
HRMS (ES+): m/z calcd for C18H29O4SSi (M + H)+: 369.1556;
found: 369.1573
Anal. Calcd for C18H28O4SSi: C, 58.66; H, 7.66. Found: C, 58.45;
H, 7.80.
1,5-Anhydro-2,6-dideoxy-3,4-di-O-tert-butyldimethylsilyl-1-
[(SS)-phenylsulfinyl]-L-arabino-hex-1-enitol [(SS)-28]
To a solution of alcohol (SS)-58 (0.94 g, 2.5 mmol) in CH2Cl2 (66
mL) at 0 °C was added DIPEA (0.74 g, 1.0 mL, 5.8 mmol) followed
by the dropwise addition of TBSOTf (0.79 g, 0.68 mL, 3.0 mmol).
After 12 h at r.t., the reaction mixture was washed with H2O (100
mL) and the aqueous layer extracted with CH2Cl2 (2 × 50 mL). The
combined organic extracts were dried (Na2SO4) and concentrated in
vacuo. The residue was purified by column chromatography (SiO2,
hexanes–Et2O) to give the 1-phenylsulfinyl glycal (SS)-28 (1.07 g,
2.2 mmol, 89%) as a white solid; mp 71–72 °C (MeOH–H2O).
[a]D28 +136 (c 1.00, CHCl3).
Figure 5 Molecular structure of (SS)-28
IR (film): 3057s, 2951s, 2928s, 2887s, 1641s, 1464s, 1246s, 1078s,
895s, 834s, 770s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.70–7.65 (2 ArH, m), 7.47–7.42
(3 ArH, m), 5.66 (1 H, dd, J = 4.5, 1.3 Hz, C2H), 4.18 (1 H, ddq, J =
6.9, 3.1, 1.5 Hz, C5H), 4.01 (1 H, ddd, J = 4.4, 2.8, 1.5 Hz, C3H),
3.60 (1 H, dt, J = 3.0, 1.3 Hz, C4H), 1.04 (3 H, d, J = 7.0 Hz,
CH3CH), 0.86 [9 H, s, (CH3)3C], 0.80 [9 H, s, (CH3)3C], 0.11 (3 H,
s, CH3Si), 0.08 (3 H, s, CH3Si), 0.04 (3 H, s, CH3Si), –0.01 (3 H, s,
CH3Si).
13C NMR (75 MHz, CDCl3): d = 155.5 (C1), 142.5 (CAr), 131.4
(CArH), 129.2 (2 CArH), 125.4 (2 CArH), 102.2 (C2H), 78.5 (C5H),
73.7 (C4H), 67.4 (C3H), 26.0 [(CH3)3C], 26.0 [(CH3)3C], 18.2 [2
C(CH3)3], 15.4 (CH3CH), –4.0 (CH3Si), –4.2 (CH3Si), –4.3
(CH3Si), –4.4 (CH3Si).
5-O-tert-Butyldimethylsilyl-1-deoxy-2,3-O-isopropylidene-1-
[(RS)-phenylsulfinyl-a-D-ribofuranose [(RS)-61] and its Epimer
(SS)-61
Oxidation of the thioether 60 (6.55 g, 16.5 mmol) with mCPBA
(4.08 g, 77%, 18.1 mmol) and NaHCO3 (16.5 g, 196 mmol) in
CH2Cl2 (70 mL) at –78 °C for 2 h according to typical procedure 4
gave sulfoxide 61 (7.0 g, 15.7 mmol, 95%) as a 1.4:1 mixture of two
epimers after column chromatography (SiO2, hexanes–Et2O). The
ratio was determined by integration of the 1H NMR signals for C4H
at d = 4.25 (major, more polar) and d = 4.48 (minor, less polar). A
second column chromatography achieved partial separation of the
epimers and gave analytical samples of pure of (RS)-61 and (SS)-61.
HRMS (ES+): m/z calcd for C24H43O4SSi2 (M + H)+: 483.2421;
found: 483.2425.
(RS)-61 (Major Epimer)
Colourless oil; [a]D23 –80 (c 0.4, CHCl3).
Anal. Calcd for C24H42O4SSi2: C, 59.70; H, 8.77. Found: C, 59.65;
H, 8.95.
IR (film): 2953s, 2931s, 2857s, 1471m, 1382m, 1255s, 1212s,
1083s 1043s, 836s cm–1.
The structure and stereochemistry of (SS)-28 were established by X-
ray crystallography (Figure 5).
1H NMR (500 MHz, CDCl3): d = 7.77–7.73 (2 ArH, m), 7.51–7.47
(3 ArH, m), 5.18 (1 H, dd, J = 6.0, 4.6 Hz, C2H), 4.86 (1 H, dd, J =
6.1, 1.3 Hz, C3H), 4.64 (1 H, d, J = 4.6 Hz, C1H), 4.25 (1 H, dt, J =
2.6, 1.2 Hz, C4H), 3.59 (1 H, dd, J = 11.1, 2.6 Hz, C5HAHB), 3.57
(1 H, dd, J = 11.1, 2.6 Hz, C5HAHB), 1.69 (3 H, s, CH3C), 1.44 (3
H, s, CH3C), 0.80 [9 H, s, (CH3)3C], –0.09 (3 H, s, CH3Si), –0.12 (3
H, s, CH3Si).
13C (75 MHz, CDCl3): d = 143.0 (CAr), 131.6 (CArH), 129.1 (2
CArH), 126.2 (2 CArH), 114.6 [C(CH3)2], 101.0 (C1H), 86.9 (C4H),
83.2 (C3H), 81.9 (C2H), 65.3 (C5H2), 26.4 (CH3C), 26.2 [(CH3)3C],
25.1 (CH3C), 18.5 [C(CH3)3], –5.3 (CH3Si), –5.4 (CH3Si).
1-Phenylsulfinyl Glycals (SS)- and (RS)-29 (Scheme 15)
Phenyl 5-O-tert-Butyldimethylsilyl-2,3-O-isopropylidene-1-
thio-a-D-ribofuranoside (61)
The reaction of 5-O-(tert-butyldimethylsilyl)-2,3-O-isopropy-
lidene-D-ribofuranose (59)45 (12.9 g, 42.0 mmol) with PhSSPh
(10.0 g, 46.0 mmol) and Bu3P (17.0 g, 21.0 mL, 84.0 mmol) in
CH2Cl2 (70 mL) according to the procedure of Fürstner46 gave, after
column chromatography (SiO2, hexanes–Et2O), the thioether 60
(11.8 g, 30.0 mmol, 71%) as a single diastereoisomer (colourless
oil). The spectroscopic data were consistent with those reported.46
HRMS (ES+): m/z calcd for C20H32O5SSiNa (M + Na)+: 435.1632;
found: 435.1639.
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2759
TBSO
TBSO
O
O
PhSSPh (1.2 equiv)
Bu3P (2 equiv)
O
O
O
O
CH2Cl2, 0 °C, then r.t.
71%
OH
SPh
59
60
MCPBA (1.1 equiv), NaHCO3 (12 equiv) 95%
CH2Cl2, –78 °C (dr 1.4:1)
TBSO
TBSO
H
O
O
H
+
O
O
O
O
O
1:1.4
S
S
Ph
Ph
O
(RS)-61 (major)
(SS)-61 (minor)
mp 73.0–74.0 °C
X-ray (Figure 6)
LDA (2.5 equiv)
THF, –78 °C
88%
TBSO
HO
TBSO
HO
O
S
+
O
S
1:1.4
Ph
O
Ph
O
Figure 6 Molecular structure of (SS)-61
(RS)-62 (major)
mp 79.0–81.0 °C
(SS)-62 (minor)
TBSCl (1.2 equiv)
imidazole (2.5 equiv)
DMF, r.t.
1,4-Anhydro-2-deoxy-5-O-tert-butyldimethylsilyl-1-[(RS)-phe-
nylsulfinyl]-D-erythro-pent-1-enitol [(RS)-62] and its Epimer
(SS)-62
72% (90% brsm)
overall from 62
TBSO
TBSO
TBSO
Reaction of sulfoxide 61 (6.2 g, 15.0 mmol, 1.4:1 mixture of diaste-
reoisomers) with LDA (2.5 equiv) in THF (114 mL) according to
typical procedure 3 gave alcohol 62 (4.66 g, 13.0 mmol, 88%) as a
colourless oil after column chromatography (SiO2, hexanes–Et2O).
Integration of the 1H NMR signals (C6D6) for C4H at d = 4.59 and
d = 4.44 indicated that the product was a 1.4:1 mixture of two
epimers (RS)-62 and (SS)-62 respectively. A second column chro-
matography achieved partial separation of the epimers and gave
analytic samples of pure (RS)-62 and (SS)-62.
TBSO
+
O
O
1:1.4
S
S
Ph
O
Ph
O
(RS)-29 (major)
(SS)-29 (minor)
Scheme 15 Synthesis of 1-phenylsulfinyl glycal (SS,RS)-29
(RS)-62 (Major Epimer)
This product was the more polar of the two and was obtained as a
white solid, with mp 79–81 °C (Et2O–hexane). This isomer decom-
posed over 24 h at r.t. in CDCl3 that had been stored over K2CO3;
therefore, spectroscopic data was best acquired in C6D6.
(SS)-61 (Minor Epimer)
White crystalline solid; mp 73–74 °C (hexane); [a]D23 +19 (c 0.78,
CHCl3).
IR (diamond compression system): 2928s, 2856s, 1471s, 1213s,
1163s cm–1.
[a]D28 +14 (c 0.84, C6H6).
IR (diamond compression system): 3374m, 2951m, 2930m, 2856m,
1600m, 1445m, 1387m, 1251m, 1108s, 1080s, 1014s, 839m cm–1.
1H NMR (500 MHz, CDCl3): d = 7.84–7.81 (2 ArH, m), 7.51–7.47
(3 ArH, m), 4.81 (1 H, d, J = 4.7 Hz, C1H), 4.80 (1 H, dd, J = 6.2,
1.5 Hz, C3H), 4.60 (1 H, dd, J = 6.2, 4.7 Hz, C2H), 4.48 (1 H, app
dt, J = 2.2, 1.7 Hz, C4H), 3.83 (1 H, dd, J = 11.1, 2.7 Hz, C5HAHB),
3.69 (1 H, dd, J = 11.1, 2.1 Hz, C5HAHB), 1.65 (3 H, s, CH3C), 1.32
(3 H, s, CH3C), 0.78 [9 H, s, (CH3)3C], 0.00 (3 H, s, CH3Si), –0.01
(3 H, s, CH3Si).
3C NMR (75 MHz, CDCl3): d = 142.2 (CAr), 131.7 (CArH), 129.2 (2
CArH), 126.2 (2 CArH), 114.5 [C(CH3)2], 102.9 (C1H), 86.5 (C4H),
83.2 (C3H), 81.5 (C2H), 65.1 (C5H2), 26.4 (CH3C), 26.1 [(CH3)3C],
25.3 (CH3C), 18.3 [C(CH3)3], –5.2 (CH3Si), –5.4 (CH3Si).
1H NMR (500 MHz, C6D6): d = 7.66 (2 ArH, d with fine splitting,
J = 7.1 Hz), 7.03 (2 ArH, t with extra splitting, J = 7.4 Hz), 6.97 (1
ArH, t with fine splitting, J = 7.3 Hz), 5.92 (1 H, d, J = 2.7 Hz,
C2H), 4.81–4.76 (1 H, m, C3H), 4.59 (1 H, ddd, J = 5.3, 5.1, 3.6 Hz,
C4H), 3.43 (1 H, d, J = 7.5 Hz, OH), 3.30 (1 H, dd, J = 11.2, 5.6 Hz,
C5HAHB), 3.27 (1 H, dd, J = 11.2, 4.9 Hz, C5HAHB), 0.82 [9 H, s,
(CH3)3C)], –0.15 (3 H, s, CH3Si), –0.18 (3 H, s, CH3Si).
13C NMR (75 MHz, C6D6): d = 163.6 (C1), 142.7 (CAr), 132.0
(CArH), 129.9 (2 CArH), 125.9 (2 CArH), 107.2 (C2H), 94.5 (C4H),
75.2 (C3H), 63.5 (C5H2), 26.5 [(CH3)3C], 18.9 [C(CH3)3], –4.92
(CH3Si), –4.95 (CH3Si).
HRMS (ES+): m/z calcd for C20H32O5SSiNa (M + Na)+: 435.1632;
found: 435.1639.
HRMS (ES+): m/z calcd for C17H27O4SSi (M + H)+: 355.1394;
found: 355.1396.
The structure and stereochemistry of the minor sulfoxide (SS)-61
was established by X-ray crystallography (Figure 6).
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2760
K. Jarowicki et al.
PAPER
Anal. Calcd for C17H26O4SSi: C, 57.63; H, 7.34. Found: C, 57.65;
H, 7.45.
(CH3)3C], –0.020 (3 H, s, CH3Si), –0.024 (3 H, s, CH3Si), –0.03 (3
H, s, CH3Si), –0.05 (3 H, s, CH3Si).
13C NMR (75 MHz, C6D6): d = 164.8 (C1), 143.2 (CAr), 132.0
(CArH), 129.8 (2 CArH), 126.1 (2 CArH), 106.2 (C2H), 93.7 (C4H),
76.1 (C3H), 63.2 (C5H2), 26.6 [(CH3)3C], 26.5 [(CH3)3C], 19.0
[C(CH3)3], 18.7 [C(CH3)3], –3.7 (CH3Si), –3.8 (CH3Si), –4.72
(CH3Si), –4.74 (CH3Si).
(SS)-62 (Minor Epimer)
Less polar; colourless oil; [a]D28 +160 (c 1.28, C6H6).
IR (film): 3387m, 2955s, 2928s, 2856s, 1618w, 1472m, 1444m,
1254s, 1084s, 837s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.75–7.69 (2 ArH, m), 7.54–7.49
(3 ArH, m), 5.81 (1 H, d, J = 2.8 Hz, C2H), 4.95–4.90 (1 H, m,
C3H), 4.46 (1 H, dt, J = 5.0, 3.5 Hz, C4H), 3.68 (1 H, dd, J = 11.1,
4.9 Hz, C5HAHB), 3.58 (1 H, dd, J = 11.1, 5.1 Hz, C5HAHB), 2.45
(1 H, br s, OH), 0.84 [9 H, s, (CH3)3C)], 0.00 (3 H, s, CH3Si), –0.02
(3 H, s, CH3Si).
13C NMR (75 MHz, CDCl3): d = 162.7 (C1), 141.0 (CAr), 132.2
(CArH), 129.7 (2 CArH), 125.7 (2 CArH), 106.9 (C2H), 93.0 (C4H),
75.0 (C3H), 62.8 (C5H2), 26.1 [(CH3)3C], 18.6 [C(CH3)3], –5.1 (2
CH3Si).
1-Phenylsulfinyl Glycals (SS)-37, (SS)-39, and (RS)-39 (Scheme
16)
BnO
H
OBn
BnO
OBn
BnO
BnO
BnO
LDA (2.5 equiv)
O
O
O
O
THF, –78 °C
93% (1.54 mmol scale)
S
S
Ph
Ph
(SS)-37
mp 105–106 °C
X-ray (Figure 7)
HRMS (ES+): m/z calcd for C17H27O4SSi (M + H)+: 355.1394;
found: 355.1406.
(SS)-63
1,4-Anhydro-2-deoxy-3,5-di-O-tert-butyldimethylsilyl-1-[(RS)-
phenylsulfinyl]-D-erythro-pent-1-enitol [(RS)-29] and its Epimer
(SS)-29
BnO
H
OBn
BnO
OBn
BnO
H
OBn
mCPBA
BnO
BnO
BnO
H
BnO
BnO
CH2Cl2
+
1.4:1
O
O
O
O
–78 °C
90%
Following typical procedure 3 described above, addition of the sul-
foxide 61 (2.06 g, 5.0 mmol, 1.4:1 mixture of epimers) to LDA (2.5
equiv) gave crude alcohol 62 (1.85 g, 5.0 mmol, 100%) as a colour-
less oil. Without purification, crude 62 was dissolved in DMF (35
mL) and treated with imidazole (0.85 g, 12.5 mmol) and TBSCl
(0.91 g, 6.0 mmol). The solution was stirred at r.t. for 12 h, then
poured into H2O (350 mL) and extracted with Et2O (2 × 100 mL).
The combined organic extracts were dried (Na2SO4) and concentrat-
ed in vacuo. The residue was purified by column chromatography
(SiO2, hexanes–Et2O) to give the title 1-phenylsulfinyl glycal 29
(1.69 g, 3.6 mmol, 72%) as an inseparable mixture of epimers and
recovered starting material 62 (0.31 g, 0.9 mmol, 18%). The ratio of
epimers was determined by integration of the 1H NMR signals (dou-
blets) for C2H at d = 5.82 ppm for (RS)-29 (major) and d = 5.87 ppm
for (SS)-29 (minor). The spectroscopic data were recorded on the
mixture of epimers.
BnO
S
S
SPh
64
Ph
Ph
O
(RS)-65
mp 119–122 °C
(SS)-65
mp 102–104 °C
LDA (2.5 equiv)
THF, –78 °C
LDA (2.5 equiv)
THF, –78 °C
93%
78%
OBn
Ph
O
S
O
BnO
BnO
OBn
TBSO
BnO
1. PPTS BnO
MeOH
O
O
O
O
O
O
2. NaH
BnBr
S
S
23%
Ph
Ph
Ph
(SS)-39
mp 98–99 °C
(RS)-36
(RS)-39
mp 70–74 °C
IR (film): 2954s, 2929s, 2886s, 2857s, 1618m, 1472s, 1253s, 1087s,
1054s, 836s, 778s cm–1.
HRMS (ES+): m/z calcd for C23H41O4SSi2 (M + H)+: 469.2259;
Scheme 16 Synthesis of 1-phenylsulfinyl glycals (SS)-37, (SS)-39 and
(RS)-39
found: 469.2253.
1,5-Anhydro-2-deoxy-3,4,6-O-phenylmethyl-1-[(SS)-phenyl-
sulfinyl]-D-lyxo-hex-1-enitol (SS)-37
(RS)-29 (Major Epimer)
1H NMR (500 MHz, C6D6): d = 7.69 (2 ArH, d with extra splitting,
J = 7.1 Hz), 7.03–6.91 (3 ArH, m), 5.82 (1 H, d, J = 2.6 Hz, C2H),
4.94 (1 H, dd, J = 3.0, 2.8 Hz, C3H), 4.49 (1 H, ddd, J = 6.1, 5.2, 3.3
Hz, C4H), 3.37 (1 H, dd, J = 11.1, 5.1 Hz, C5HAHB), 3.22 (1 H, dd,
J = 11.0, 6.2 Hz, C5HAHB), 0.90 [9 H, s, (CH3)3C], 0.83 [9 H, s,
(CH3)3C], 0.009 (3 H, s, CH3Si), 0.012 (3 H, s, CH3Si), –0.11 (3 H,
s, CH3Si), –0.13 (3 H, s, CH3Si).
Reaction of sulfoxide (SS)-6347 (1.00 g, 1.54 mmol) with LDA (2.5
equiv) according to typical procedure 3 gave a crude product that
was purified by column chromatography (SiO2, hexanes–Et2O) to
give the 1-phenylsulfinyl galactal (SS)-37 (0.77 g, 1.43 mmol, 93%)
as a white solid; mp 105–106 °C (Et2O).
[a]D23 –66 (c 0.924, CHCl3).
IR (film): 1454m, 1353m, 1052s, 733s, 695s cm–1.
13C NMR (75 MHz, C6D6): d = 164.5 (C1), 143.5 (CAr), 131.6
(CArH), 129.7 (2 CArH), 125.7 (2 CArH), 106.7 (C2H), 93.5 (C4H),
76.2 (C3H), 62.7 (C5H2), 26.6 [(CH3)3C], 26.5 [(CH3)3C], 19.0
[C(CH3)3], 18.7 [C(CH3)3], –3.7 (CH3Si), –3.9 (CH3Si), –4.9 (2
CH3Si).
1H NMR (300 MHz, CDCl3): d = 7.59–7.55 (2 ArH, m), 7.37–7.12
(18 ArH, m), 5.76 (1 H, dd, J = 2.6, 1.3 Hz, C2H), 4.81 (1 H, d, J =
11.6 Hz, CHAHBPh), 4.65 (1 H, d, J = 12.0 Hz, CHAHBPh), 4.55 (1
H, d, J = 12.3 Hz, CHAHBPh), 4.46 (1 H, d, J = 12.3 Hz, CHAHBPh),
4.29 (1 H, d, J = 11.7 Hz, CHAHBPh), 4.23 (1 H d, J = 12.5 Hz,
CHAHBPh), 4.21 (1 H, ddd, J = 4.9, 2.8, 1.1 Hz, C3H), 4.12 (1 H,
tdd, J = 6.4, 2.0, 1.0 Hz, C5H), 3.87 (1 H, app quintet, J = 2.0 Hz,
C4H), 3.55 (2 H, d, J = 6.4 Hz, C6H2).
(SS)-29 (Minor Epimer)
1H NMR (500 MHz, C6D6): d = 7.74 (2 ArH, d with extra splitting,
J = 7.1 Hz), 7.03–6.91 (3 ArH, m), 5.87 (1 H, d, J = 2.7 Hz, C2H),
4.99 (1 H, t, J = 3.0 Hz, C3H), 4.40 (1 H, ddd, J = 5.3, 5.1, 3.3 Hz,
C4H), 3.48 (1 H, dd, J = 11.1, 4.9 Hz, C5HAHB), 3.40 (1 H, dd, J =
11.4, 5.8 Hz, C5HAHB), 0.90 [9 H, s, (CH3)3C], 0.86 [9 H, s,
13C NMR (75 MHz, CDCl3): d = 156.2 (C1), 141.9 (CAr), 138.5
(CAr), 138.1 (CAr), 131.3 (CArH), 129.2 (2 CArH), 128.8 (2 CArH),
128.7 (2 CArH), 128.6 (2 CArH), 128.2 (CArH), 128.1 (4 CArH),
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2761
128.04 (2 CArH), 127.95 (CArH), 127.9 (2 CArH), 125.4 (2 CArH),
103.2 (C2H), 78.9 (C5H), 74.0 (CH2Ph), 73.7 (CH2Ph), 72.1 (C3H),
71.5 (CH2Ph), 71.0 (C4H), 67.7 (C6H2).
HRMS (ES+): m/z calcd for C33H32O5SNa (M + Na)+: 563.1863;
69.2 (C6H2). Signals for 4 carbons in the aromatic region could not
be distinguished.
HRMS (ES+): m/z calcd for C40H40O6SNa (M + Na)+: 671.2438;
found: 671.2451.
found: 563.1858.
Sulfoxide (RS)-65 failed to give a satisfactory microanalysis.
Anal. Calcd for C33H32O5S: C, 73.31; H, 5.97; S, 5.93. Found: C,
73.05; H, 5.95; S, 5.80.
(SS)-65
20
Mp 102–104 °C (MeOH) (Lit.47 mp 101–102 °C); [a]D +18 (c
The structure and stereochemistry of (SS)-37 was established by X-
ray crystallography (Figure 7).
0.612, CHCl3) {Lit.47 [a]Hg23 +39.0 (c CHCl3)}.
IR (film): 1452m, 1093s, 1036s, 744s, 698s cm–1.
1H NMR (500 MHz, CDCl3): d = 7.60–7.59 (2 ArH, m), 7.39–7.24
(19 ArH, m), 7.19–7.16 (4 ArH, m), 4.83 (2 H, s, CH2Ph), 4.82 (1
H, d, J = 10.9 Hz, CHAHBPh), 4.78 (1 H, d, J = 10.9 Hz, CHAHBPh),
4.74 (1 H, d, J = 10.9 Hz, CHAHBPh), 4.52 (1 H, d, J = 10.9 Hz,
CHAHBPh), 4.49 (1 H, d, J = 8.8 Hz, C1H), 4.45 (2 H, s, CH2Ph),
3.80 (2 H, m, C2H + C3H or C4H), 3.73 (2 H, d, J = 2.6 Hz, C6H2),
3.63–3.56 (2 H, m, C5H + C3H or C4H).
13C NMR (75 MHz, CDCl3): d = 140.4 (CAr), 138.5 (CAr), 138.3
(CAr), 138.2 (CAr), 138.0 (CAr), 131.4 (CArH), 129.1 (2 CArH),
128.83 (2 CArH), 128.80 (2 CArH), 128.7 (2 CArH), 128.6 (2 CArH),
128.3 (2 CArH), 128.21 (CArH), 128.16 (CArH), 128.1 (2 CArH),
128.0 (CArH), 128.00 (2 CArH), 127.96 (2 CArH), 126.0 (2 CArH),
95.8 (C1), 86.6 (CH), 79.6 (CH), 77.6 (CH), 76.6 (CH), 75.7 (CH2),
75.2 (CH2), 74.2 (CH2), 73.9 (CH2), 68.9 (C6H2). A signal for 1 car-
bon could not be distinguished.
HRMS (ES+): m/z calcd for C40H40O6SNa (M + Na)+: 671.2438;
found: 671.2443.
Anal. Calcd for C40H40O6S: C, 74.05; H, 6.21; S, 4.94. Found: C,
73.80; H, 6.20; S, 4.75.
Figure 7 Molecular structure of (SS)-37
1,5-Anhydro-3,4,6-tri-O-phenylmethyl-1,2-dideoxy-1-[(RS)-
phenylsulfinyl]-D-arabino-hex-1-enitol [(RS)-39] and its Epimer
(SS)-39
Treatment of sulfoxide (RS)-65 (2.0 g, 3.0 mmol) with LDA (2.6
equiv) in THF at –78 °C according to typical procedure 3 outlined
above gave (RS)-39 (1.55 g, 2.9 mmol, 93%) as a white solid after
purification by column chromatography (SiO2, hexanes–EtOAc). A
sample recrystallised from EtOAc–hexanes gave mp 70–74 °C.
1-Deoxy-2,3:4,6-tetra-O-phenylmethyl-1-[(RS)-phenylsulfinyl]-
b-D-glucopyranoside [(RS)-65] and its Epimer (SS)-65
Oxidation of phenyl 2,3,4,6-tetra-O-benzyl-1-thio-b-gluco-
pyranoside48 (64) (7.2 g, 11.4 mmol) with mCPBA according to
typical procedure 4 gave a mixture of diastereoisomeric sulfoxides
(RS)-65 and (SS)-65 in the ratio 1.4:1 according to integration of the
1H NMR signal at d = 4.32 for (RS)-65 and 4.53 for (SS)-65. The
mixture was separated by column chromatography (SiO2, hexanes–
EtOAc) to give first the major diastereoisomer (RS)-65 (1.97 g, 3.04
mmol, 27%), then a mixture of the diastereoisomers (2.15 g, 3.31
mmol, 29%), and finally the minor diastereoisomer (SS)-65 (2.51 g,
3.87 mmol, 34%).
[a]D23 –150 (c 0.6 CHCl3) {Lit.47 [a]Hg22 –116.9 (c 1.0 CHCl3)}.
IR (film): 1637m, 1452m, 1300m, 1097s, 1048s, 845m, 741s, 694s,
530m cm–1.
1H NMR (500 MHz, CDCl3): d = 7.74–7.73 (2 ArH, m), 7.46–7.41
(3 ArH, m), 7.34–7.22 (13 ArH, m), 7.12–7.10 (2 ArH, m), 5.92 (1
H, d, J = 3.0 Hz, C2H), 4.73 (1 H, d, J = 11.5 Hz, CHAHBPh), 4.68
(1 H, d, J = 11.5 Hz, CHAHBPh), 4.60 (1 H, d, J = 11.5 Hz,
CHAHBPh), 4.55 (1 H, d, J = 11.5 Hz, CHAHBPh) 4.30–4.27 (2 H,
m, C3H and C5), 4.22 (1 H, d, J = 12.0 Hz, CHAHBPh), 4.17 (1 H,
d, J = 12.0 Hz, CHAHBPh), 4.81 (1 H, app t, J = 6.0 Hz, C4H), 3.58–
3.52 (2 H, m, C6H2).
13C NMR (75 MHz, CDCl3): d = 157.8 (C1), 142.4 (CAr), 138.3
(CAr), 138.1 (CAr), 138.0 (CAr), 131.9 (CArH), 129.4 (2 CArH), 128.9
(2 CArH), 128.8 (2 CArH), 128.6 (2 CArH), 128.2 (4 CArH), 127.9
(CArH), 127.7 (2 CArH), 125.9 (2 CArH), 99.3 (C2H), 80.2 (C5H),
74.3 (C3H and C4H), 73.8 (CH2), 73.5 (CH2), 71.2 (CH2), 68.0
(C6H2).
(RS)-65
Mp 119–122 °C (MeOH) (Lit.47 mp 116–117 °C); [a]D20 –48 (c 1.1,
CHCl3) {Lit.47 [a]Hg23 –94.0 (c CHCl3)}.
IR (film): 3031m, 2871m, 1452s, 1361s, 1154s, 1037s, 732s, 696s
cm–1.
1H NMR (300 MHz, CDCl3): d = 7.67–7.63 (2 ArH, m), 7.47–7.24
(19 ArH), 7.19–7.17 (4 ArH, m), 5.03 (1 H, d, J = 10.2 Hz,
CHAHBPh), 4.97 (1 H, d, J = 11.0 Hz, CHAHBPh), 4.97 (1 H, d, J =
11.0 Hz, CHAHBPh), 4.91 (1 H, d, J = 11.0 Hz, CHAHBPh), 4.80 (1
H, d, J = 11.0 Hz, CHAHBPh), 4.58 (1 H, d, J = 10.7 Hz, CHAHBPh),
4.32 (1 H, d, J = 12.0 Hz, CHAHBPh), 4.21 (1 H, d, J = 12.0 Hz,
CHAHBPh), 4.11 (1 H, t, J = 9.3 Hz, C2H), 3.98 (1 H, d, J = 9.7 Hz,
C1H), 3.80 (1 H, t, J = 9.0 Hz, C3H), 3.57 (1 H, t, J = 9.5 Hz, C4H),
3.53–3.48 (2 H, m, C6H2), 3.35–3.29 (1 H, m, C5H).
3C NMR (75 MHz, CDCl3): d = 139.9 (CAr), 138.6 (CAr), 138.1
(CAr), 137.9(CAr), 131.3 (CArH), 129.2 (2 CArH), 128.91(2 CArH),
128.87 (2 CArH), 128.8 (2 CArH), 128.6 (2 CArH), 128.5 (CArH),
128.4 (2 CArH), 128.3 (CArH), 128.13 (CArH), 128.0 (2 CArH), 127.9
(2 CArH), 125.6 (2 CArH), 93.8 (C1H), 86.9 (C3H), 81.1 (C5H), 77.9
(C4H), 77.2 (C2H), 76.2 (CH2), 76.0 (CH2), 75.5 (CH2), 73.8 (CH2),
HRMS (ES+): m/z calcd for C33H32NaO5S (M + Na)+: 563.1863;
found: 563.1870.
Anal. Calcd for C33H32O5S: C, 73.31; H, 5.97; S, 5.93. Found: C,
73.30; H, 6.10; S, 5.70.
(SS)-39
Similarly, treatment of sulfoxide (SS)-65 (2.5 g, 3.85 mmol) with
LDA (2.5 equiv) in THF at –78 °C according to typical procedure 4
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

2762
K. Jarowicki et al.
PAPER
gave (SS)-39 (1.63 g, 3.0 mmol, 78%) as a white solid after purifi-
cation by column chromatography (SiO2, hexanes–EtOAc). A sam-
ple recrystallised from EtOAc–hexanes gave white needles; mp 98–
99 °C.
References
(1) (a) Jarosz, S.; Zamojski, A. Curr. Org. Chem. 2003, 7, 13.
(b) Somsák, L. Chem. Rev. 2001, 101, 81.
(2) (a) Friesen, R. W.; Loo, R. W. J. Org. Chem. 1991, 56,
4821. (b) Dubois, E.; Beau, J.-M. Carbohydr. Res. 1992,
223, 157.
(3) Dubois, E.; Beau, J.-M. Carbohydr. Res. 1992, 228, 103.
(4) Tius, M. A.; Gomez-Galeno, J.; Gu, X.-q. Z.; Javid, H.
J. Am. Chem. Soc. 1991, 113, 5775.
[a]D20 +21 (c 1.30, CHCl3) {Lit.47 [a]Hg22 +16.3 (c 1.0 CHCl3)}.
IR (film): 3027m, 2900m, 2858m, 1655m, 1453m, 1273m, 1122s,
1090s, 868m, 731s, 694s, 612m cm–1.
1H NMR (500 MHz, CDCl3): d = 7.71–7.70 (2 ArH, m), 7.45–7.39
(3 ArH, m), 7.33–7.25 (11 ArH, m), 7.21–7.16 (4 ArH, m), 5.91 (1
H, d, J = 3.0 Hz, C2H), 4.75 (1 H, d, J = 11.1 Hz, CHAHBPh), 4.71
(1 H, d, J = 11.5 Hz, CHAHBPh), 4.60 (1 H, d, J = 11.5 Hz,
CHAHBPh), 4.56 (1 H, d, J = 11.6 Hz, CHAHBPh), 4.38 (2 H, s,
CH2Ph), 4.28 (1 H, dd, J = 6.4, 3.0 Hz, C3H), 4.04–4.01 (1 H, m,
C5H), 3.91 (1 H, dd, J = 8.6, 6.5 Hz, C4H), 3.78 (1 H, dd, J = 11.6,
4.7 Hz, C6HAHB), 3.67 (1 H, dd, J = 11.6, 2.6 Hz, C6HAHB).
13C NMR (75 MHz, CDCl3): d = 157.7 (C1), 142.1(CAr), 138.23
(CAr), 138.20 (CAr), 138.0 (CAr), 131.7 (CArH), 129.4 (2 CArH),
128.8 (2 CArH), 128.6 (4 CArH), 128.2 (2 CArH), 128.0 (2 CArH),
127.9 (CArH), 127.8 (2 CArH), 125.4 (2 CArH), 101.1 (C2H), 80.0
(C5H), 75.7 (C3H), 74.4 (C4H), 74.0 (CH2), 73.6 (CH2), 71.2
(CH2), 68.0 (C6H2). Signals for 2 carbons could not be distin-
guished.
(5) Zhang, H.-C.; Brakta, M.; Doyle Daves, G. Tetrahedron
Lett. 1993, 34, 1571.
(6) Koo, B.; McDonald, F. E. Org. Lett. 2005, 7, 3621.
(7) Steunenberg, P.; Jeanneret, V.; Zhu, Y.-H.; Vogel, P.
Tetrahedron Asymmetry 2005, 16, 337.
(8) Dubbaka, S. R.; Steunenberg, P.; Vogel, P. Synlett 2004,
1235.
(9) Lesimple, P.; Beau, J.-M.; Sinaÿ, P. J. Chem. Soc., Chem.
Commun. 1985, 894.
(10) Hanessian, S.; Martin, M.; Desai, R. C. J. Chem. Soc., Chem.
Commun. 1986, 926.
(11) Bearder, J. R.; Dewis, M. L.; Whiting, D. A. J. Chem. Soc.,
Perkin Trans.1 1995, 227.
(12) Parker, K. A.; Su, D.-S. J. Carbohydr. Chem. 2005, 24, 187.
(13) (a) Parker, K. A.; Coburn, C. A.; Koh, Y. J. Org. Chem.
1995, 60, 2938. (b) Koyama, Y.; Yamaguchi, R.; Suzuki, K.
Angew. Chem. Int. Ed. 2008, 47, 1084.
(14) Dötz, K. H.; Otto, F.; Nieger, M. J. Organomet. Chem. 2001,
621, 77.
(15) Hallett, M. R.; Painter, J. E.; Quayle, P.; Ricketts, D.
Tetrahedron Lett. 1998, 39, 2851.
(16) Milne, J. E.; Jarowicki, K.; Kocienski, P. J.; Alonso, J.
HRMS (ES+): m/z calcd for C33H33O5S (M + H)+: 541.2043; found:
541.2052.
Sulfoxide (SS)-39 failed to give a satisfactory microanalysis. Nei-
ther (RS)-39 nor (SS)-39 gave crystals suitable for X-ray diffraction.
Therefore the stereochemistry of the 1-phenylsulfinyl glycal (RS)-
39 was established by a chemical correlation with (RS)-36 whose
stereochemistry had been established (see Scheme 11 above).
Chem. Commun. 2002, 426.
(17) Review: Friesen, R. W. J. Chem. Soc., Perkin Trans. 1 2001,
1969.
(18) Boeckman, R. K.; Bruza, K. J. Tetrahedron 1981, 37, 3997.
(19) Glycals with heteroatom substituents (Cl, OR, SR) at C2
rapidly metallate with n-BuLi, conditions that are
compatible with benzyl ether protecting groups: Boyd, E.;
Hallet, M. R.; Jones, R. V. H.; Painter, J. E.; Patel, P.;
Quayle, P.; Waring, A. J. Tetrahedron Lett. 2006, 47, 8337;
and references cited therein.
(20) Friesen, R. W.; Sturino, C. F.; Daljeet, A. K.; Kolaczewska,
A. J. Org. Chem. 1991, 56, 1944.
(21) (a) Friesen, R. W.; Trimble, L. A. J. Org. Chem. 1996, 61,
1165. (b) Imanieh, H.; Quayle, P.; Voaden, M.; Street, S. D.
A. Tetrahedron Lett. 1992, 33, 543. (c) Crich, D.; Ritchie,
T. J. Tetrahedron 1988, 44, 2319.
(22) Jäkel, C.; Dötz, K. H. J. Organomet. Chem. 2001, 624, 172.
(23) Paquette, L. A.; Oplinger, J. A. Tetrahedron 1989, 45, 107.
(24) Majumder, U.; Cox, J. M.; Johnson, H. W. B.; Rainier, J. D.
Eur. J. Org. Chem. 2006, 12, 1736.
(25) (a) Friesen, R. W.; Loo, R. W.; Sturino, C. F. Can. J. Chem.
1994, 72, 1262. (b) Jäkel, C.; Dötz, K. H. Tetrahedron 2000,
56, 2167.
(26) Parker, K. A.; Su, D.-S. J. Org. Chem. 1996, 61, 2191.
(27) Lesimple, P.; Beau, J.-M.; Jaurand, G.; Sinaÿ, P.
Tetrahedron Lett. 1986, 27, 6201.
(28) Gunn, A.; Jarowicki, K.; Kocienski, P.; Lockhart, S.
Synthesis 2001, 331.
(29) The Bu3SnMgBr was prepared by transmetallation of
Bu3SnLi with MgBr2. The Bu3SnLi was prepared, in turn, by
the reaction of BuLi with Bu3SnSnBu3 thereby generating 1
equiv of Bu4Sn waste for each equiv of Bu3SnLi.
(30) Parker and Su (reference 26) reported a successful
metallation of the bis-TBS-protected analogue of 35 using 3
equiv of t-BuLi in THF at –78 °C.
Conversion of (RS)-36 into (RS)-39
A solution of the sulfoxide (RS)-36 (100 mg, 0.21 mmol) and PPTS
(53 mg, 0.21 mmol) in MeOH (6 mL) and THF (1 mL) was refluxed
for 2 d. The solvent was removed in vacuo and the residue was dis-
solved in anhyd DMF (0.4 mL) and added dropwise via syringe to
a stirred suspension of NaH (55% in mineral oil, 46 mg, ca. 1.05
mmol) in DMF (0.6 mL) at 0 °C. Then a solution of benzyl bromide
(144 mg, 0.1 mL, 0.84 mmol) in DMF (0.4 mL) was added dropwise
at 0 °C. The cooling bath was removed and the mixture was allowed
to stir at r.t. for 4 h. The reaction was quenched with H2O (5 mL)
and extracted with Et2O (3 × 10 mL). The combined organic layers
were dried over Na2SO4 and the solvent removed in vacuo. The res-
idue was purified by column chromatography (SiO2, hexanes–Et2O)
to give the 1-phenylsulfinyl glycal (RS)-39 (26 mg, 0.0481 mmol,
23% over two steps) as a white solid. The 1H and 13C NMR spectro-
scopic data were identical to those recorded for sulfoxide (RS)-39
prepared from (RS)-65 as shown in Scheme 16.
Primary Data for this article are available online at http://
www.thieme-connect.com/ejournals/toc/synthesis (added August
26th, 2009) and can be cited using the following DOI:
10.4125/pd0001th.
FIDs and associated files for the 1H, 13C and DEPT NMR spectra for
compounds 14, (SS)-23, (SS)-25, (RS)-26, 27, (SS)-28, (RS,SS)-29, 30,
(RS)-36, (SS)-36, (SS)-37, 38, (RS)-39, (SS)-39, (SS)-44, (RS)-46, (SS)-
46, (RS)-48, (SS)-48, (SS)-49, 52, (RS)-53, (RS)-55, (RS)-57, (SS)-57,
(SS)-58, (RS)-61, (SS)-61, (RS)-62, (SS)-62, (RS)-65 and (SS)-65 are
summarized.
Acknowledgment
We thank the Carnegie Trust for a studentship (J.E.M.) and the
Wellcome Trust for a studentship (V.C.).
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York

PAPER
1-Tributylstannyl Glycals from 1-Phenylsulfinyl Glycals
2763
(31) Furukawa, N.; Sato, S. In Topics in Current Chemistry, Vol.
205; Page, P. C. B., Ed.; Springer: Berlin, 1999, 89–129.
(32) Theobald, P.; Okamura, W. H. J. Org. Chem. 1990, 55, 741.
(33) (a) Lockard, J. P.; Schroeck, C. W.; Johnson, C. R. Synthesis
1973, 485. (b) Durst, T.; LeBelle, M. J.; Elzen, R. v. d.; Tin,
K. C. Can. J. Chem. 1974, 52, 761. (c) Clayden, J.; Mitjans,
D.; Youssef, L. H. J. Am. Chem. Soc. 2002, 124, 5266.
(34) Sakurada, J.; Satoh, T. Tetrahedron 2007, 63, 3806.
(35) Blakemore, P. R.; Burge, M. S. J. Am. Chem. Soc. 2007, 129,
3068.
37]. Copies of these data can be obtained, free of charge, on
application to CCDC, 12 Union Road, Cambridge CB2 1EZ,
UK; fax: +44(1223)336033 or e-mail:
deposit@ccdc.cam.ac.uk or via www.ccdc.cam.ac.uk/conts/
retrieving.html.
(41) Fernández-Mayoralas, A.; Marra, A.; Trumtel, M.;
Veyrieres, A.; Sinaÿ, P. Carbohydr. Res. 1989, 188, 81.
(42) Chen, X.-T.; Bhattacharya, S. K.; Zhou, B.; Gutteridge, C.
E.; Pettus, T. R. R.; Danishefsky, S. J. J. Am. Chem. Soc.
1999, 121, 6563.
(36) Hoffmann, R. W. Chem. Soc. Rev. 2003, 32, 225.
(37) Satoh, T. Chem. Rev. 1996, 96, 3303.
(38) Carpintero, M.; Nieto, I.; Fernández-Mayoralas, A. J. Org.
(43) Yu, W.; Jin, Z. J. Am. Chem. Soc. 2002, 124, 6576.
(44) Nicolaou, K. C.; Trujillo, J. I.; Chibale, K. Tetrahedron
1997, 53, 8751.
Chem. 2001, 66, 1768.
(39) Lipton, M. F.; Sorenson, C. M.; Sadler, A. C.; Shapiro, R. H.
J. Organomet. Chem. 1980, 186, 155.
(40) Crystallographic data for the structures in this paper have
been deposited at the Cambridge Crystallographic Data
Centre as supplementary publication nos. CCDC 685328
[(SS)-44], 676297 [(RS)-36], 676296 [(RS)-48], 676300
[(RS)-55], 676298 [(SS)-28], 676301 [(SS)-61], 682926 [(SS)-
(45) Jin, Y. H.; Liu, P.; Wang, J.; Baker, R.; Huggins, J.; Chu, C.
K. J. Org. Chem. 2003, 68, 9012.
(46) Fürstner, A. Liebigs Ann. Chem. 1993, 1211.
(47) Kast, J.; Hoch, M.; Schmidt, R. R. Liebigs Ann. Chem. 1991,
481.
(48) Damager, I.; Olsen, C. E.; Moller, B. L.; Motawia, M. S.
Carbohyr. Res. 1999, 320, 19.
Synthesis 2008, No. 17, 2747–2763 © Thieme Stuttgart · New York