Reductive decomplexation of π-allyltricarbonyliron lactone complexes using sodium naphthalenide as a route to stereodefined 1,7-diols and 2,3-diene-l,7-diols

Article abstract of DOI:10.1039/b306861g

Treatment of π-allyltricarbonyliron lactone complexes, that contain an adjacent leaving group, with lithium naphthalenide causes decomplexation to acyclic dienols in excellent yield and without any stereochemical scrambling of the allylic centre. When an endo complex is employed (E,E)-geometry prevails with good selectivity whereas (Z,E)-geometry dominates in the case of exo complexes. A mechanism consistent with the observed stereo- and regiochemistry is proposed.

Full text of DOI:10.1039/b306861g

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Reductive decomplexation of ꢀ-allyltricarbonyliron lactone
complexes using sodium naphthalenide as a route to stereodefined
1,7-diols and 2,3-diene-1,7-diols
Christopher J. Hollowood and Steven V. Ley*
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge,
UK CB2 1EW. E-mail: svl1000@cam.ac.uk; Fax: ϩ44 (01223) 336442;
Tel: ϩ44 (0)1223 336398
Received 19th June 2003, Accepted 28th July 2003
First published as an Advance Article on the web 13th August 2003
Treatment of π-allyltricarbonyliron lactone complexes, that contain an adjacent leaving group, with lithium
naphthalenide causes decomplexation to acyclic dienols in excellent yield and without any stereochemical scrambling
of the allylic centre. When an endo complex is employed (E,E)-geometry prevails with good selectivity whereas
(Z,E)-geometry dominates in the case of exo complexes. A mechanism consistent with the observed stereo- and
regiochemistry is proposed.
method. By screening of a number of reagents we found that
Introduction
lithium dimethylcuprate caused the stereo-controlled removal
Organometallic complexes are important templates for organic
of the iron unit. Thus treatment of the complex with the
synthesis programmes.1 In particular π-allyltricarbonyliron
reagent at Ϫ78 ЊC in THF for 12 hours followed by warming to
lactone complexes 1 (Fig. 1) are especially useful as they
room temperature afforded a mixture of dienes which had
undergo a wide range of chemical transformations. The stabil-
apparently formed via elimination of the appended hydroxyl
group rather than the anticipated decarboxylation of the
lactone tether. Hydrogenation of this mixture produced the
symmetrical molecule undecan-6-ol 3, which also confirms
ity of these compounds compares favourably with the related
η4-dienetricarbonyliron complexes but their real advantage lies
in the greater selectivities achieved in stereocontrolled reactions
and the extent of synthetically useful processes available for
the regio-chemistry of the reductive process (Scheme 1).
removal of the metal template.2
Fig. 1 General structure of π-allyltricarbonyliron lactone complexes.
Scheme 1 Reagents and conditions: For 2a (i) LiCuMe2, THF Ϫ78 ЊC
to rt; (ii) H2, Pd/C, EtOAc, 78%. For 2b (i) Lithium naphthalenide,
To date four main methods have been reported for this
decomplexation; barium hydroxide mediated decarboxylation
followed by oxidative release of the organic ligand affords
(E,E)-dienes;3 exhaustive carbonylation gives δ-lactones;3
single electron oxidation gives rise to δ- or β-lactones4 and
borohydride reagents provide enediols.5 All of these methods
have been employed successfully by our group in the synthesis
of natural products and bioactive materials.2,6
New and selective methods for detaching the iron carbonyl
unit leading to functionalised products would also be useful in
other synthesis programmes. Furthermore, the mechanistic
knowledge derived could aid in the design of new complexes for
future applications. In addition the observation that highly
selective hydride, alkyl and allyl additions to ketones adjacent
to the allyl system in the complexes and that Mukaiyama aldol
reactions of appended silyl enol ethers, allow access to polyol
fragments in the periphery of the organic ligand, enhances
these programmes considerably.7–10 Here we report in full, a new
method of detachment that leads to dienols and eventually
stereodefined alcohols.11
THF Ϫ78 ЊC to rt; (ii) H2, Pd/C, EtOAc, 92%.
On consideration of a possible mechanism for this cuprate
decomplexation reaction it seemed that the cuprate was acting
as a single electron reductant and that the iron by-product was
most likely to be dilithium tetracarbonylferrate [Li2Fe(CO)4],
the analogous sodium salt being well known in the literature.12
Four electron equivalents would be required mechanistically if
this were the case and indeed, the observation that at least four
equivalents were necessary to complete the conversion sup-
ported this conclusion. In order to optimise this process further
we concentrated on two main ideas. Firstly, a better leaving
group than an appended alcohol would be sensible. Secondly, if
a copper species was binding to the hydroxyl group and corre-
spondingly aiding its ability to leave, a stronger single electron
reductant may be more appropriate. Accordingly we investi-
gated the use of lithium naphthalenide as the reductant. More-
over, as iron complexes bearing acetates are readily prepared
from the corresponding alcohols, in high yield, we examined
these as suitable precursors as they contain an improved leaving
group. Therefore, lactone complex 2b was prepared and treated
with lithium naphthalenide in THF at Ϫ78 ЊC for 12 hours
followed by warming to room temperature. Hydrogenation of
the product afforded undecan-6-ol 3 as before but in a much
improved 92% yield (Scheme 1).
Results and discussion
The known iron lactone complex 2a5 was chosen as the initial
starting material for this search for a new decomplexation
T h i s j o u r n a l i s © T h e R o y a l S o c i e t y o f C h e m i s t r y 2 0 0 3
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
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Lithium naphthalenide was therefore established as the
method of choice for the reduction process. Next a range of
substrates were prepared following methods developed by our
group giving access to 1,3-dihydroxy functionality adjacent to
the iron moiety.7–10 It was thought that these complexes would
provide interesting substrates to investigate the lithium naph-
thalenide decomplexation technique as the stereogenic centres
would be retained either side of the diene formed. Their prep-
aration involves a Mukaiyama aldol reaction followed by
reduction of the carbonyl group to afford the 1,3 diol feature.
Whilst this reduction with a protected β-hydroxyl group was
known from our previous work using alkyl aluminium hydride
transfer reagents,10 when a free hydroxyl was present, the reac-
tion failed. As this was an important feature, an alternative
reduction method was sought. Since borohydride reagents,
most notably sodium triacetoxyborohydride, could be employed
to decomplex these iron carbonyl complexes at room temper-
ature over 2–3 days9c it was thought that there was scope to use
these reagents at lower temperature. Thus treatment with
sodium borohydride of the iron carbonyl complexes bearing
ketone groups in the side chain proceeded in high yield and
excellent diastereoselectivity at Ϫ78 ЊC. In these reactions it was
necessary to quench well before room temperature to avoid any
decomplexation. This method worked well for ketones with an
unprotected β-hydroxyl but was low yielding when the hydroxyl
was protected. The method therefore proved to be compli-
mentary to the previously reported hydride transfer method
(Scheme 2).
8a–9b the reaction proceeded smoothly and in excellent overall
yield to give 16a–19b. It was also possible to use an alternative
procedure for the diacetate precursors 8a,b. Namely, using
an excess of lithium naphthalenide followed by a methanol
work-up led to hydrolysis of the remaining acetate to furnish
unprotected diols 16a,b in good yield. When a mesylate was
used in place of an acetate group 10 the reaction yielded no
isolable product on a 0.15 mmol scale. The cyclic carbonate 12a
underwent the same elimination with the loss of CO2 to give an
unprotected 1,7-alkanediol 16b.
From a detailed analysis of the 1H 600 MHz NMR spectra of
the isolated mixtures of dienes from decomplexations carried
out with lithium naphthalenide, three components were identi-
fied. Calculation of the coupling constants indicated that these
three components were (2E,4E), (2Z,4E), (2E,4Z) in all cases
where the allylic alcohol is 1-C (Fig. 2). These mixtures
represented almost total mass recovery (92–98% yield) and
therefore their NMR spectra could be viewed as reasonably
accurate representations of the reaction’s selectivity. In total six
examples were studied. In the case of endo complexes with acet-
ate leaving groups 8b–9a,11a the main component was found to
be (2E,4E) 13a–d with approximately equal amounts of
(2Z,4E) 14a–d and (2E,4Z) 15a–d. For cyclic carbonates it had
been hoped that the increased conformational strain would
result in greater diastereoselectivity. Indeed this was the case, no
(2E,4Z) 15e isomer was observed and the yield of the other two
components increased 13e,14e. When an exo iron lactone com-
plex was employed 9b the major product switched from (2E,4E)
13c to (2Z,4E) 14c. Three components were still present with
the minor two being the same geometry as previously observed.
Fig. 2 Diene geometries recorded after demetallation.
Before any mechanism could be proposed it was important to
establish that the allylic centre had not been epimerised as had
been observed with some reagents that were screened in the
development of the NaBH(OAc)3 decomplexation method. It
Scheme 2 Reagents and conditions: (i) NaBH4 (10 eq.), MeOH–
CH2Cl2 (1 : 1), Ϫ78 ЊC, quenched with precooled (Ϫ78 ЊC) AcOH–
THF; (ii) Al(i-Bu)3, C6H6, 0 ЊC.
1
was thought that H NMR analysis of 1,7-alkane diols would
not reveal if any epimerisation had occurred as the stereogenic
centres were distant from one another. Complex 9a with a more
proximal stereogenic centre was prepared and subjected to
decomplexation with lithium naphthalenide and alkene hydro-
genation. No loss in stereochemical integrity was observed as
determined by 1H 600 MHz NMR spectra of 18. The epimeric
exo complex 9b was also submitted to the decomplexation
conditions and again no epimerisation was observed.
In terms of a mechanistic rational, addition of two electrons
to an iron lactone complex could result in the 18 electron
σ-bonded intermediate 20 (Scheme 3). Complexes of this
nature have been cited in other mechanisms for the reaction of
these complexes.5b If the leaving group aligns itself with the
π-system of the olefin, which in turn retains its E-configuration,
then four possible conformations can be proposed for the elim-
ination: s-cis, s-cis with the leaving group anti-periplanar to the
Fe–C bond 21a, s-cis, s-trans with the leaving group syn-peri-
planar to the Fe–C bond 21b, s-trans, s-trans with the leaving
group anti-periplanar to the Fe–C bond 21c and finally s-trans,
s-cis with the leaving group syn-periplanar to the Fe–C bond
21d. There appear to be two areas where significant steric clash
can occur: firstly between the endo substituent on the iron com-
plex and the allylic-acetate when the bond nearest the ferrate
species is s-cis, 21a and 21b, and secondly between the carbonyl
ligands and the allylic-acetate when the bond nearest the ferrate
Using these methods, a range of 1,3-dihydroxy iron com-
plexes were prepared in order to investigate the new decomplex-
ation protocol (Table 1).
In all cases it was necessary to protect the outer hydroxyl
group prior to formation of the required acetate adjacent to the
iron moiety. In the simplest cases 8a–9b, the acetoxy com-
pounds were prepared under standard conditions and in
excellent yield. Silicon based protecting groups were used to
selectively protect the outer hydroxyl in other examples. The
internal hydroxyl group was then converted to a mesylate 10 or
an acetate as in 11a or via one-pot procedure to give 11b.
Finally cyclic carbonate compounds were prepared using 1,1-
carbonyl diimidazole [CDI] 12a–c, although only one of these,
12a, was subsequently subjected to the decomplexation condi-
tions. These compounds were prepared for two reasons: firstly,
they would provide an alternative substrate where orthogonal
protection of the 1,7-dihydroxy decomplexation product was
not required and secondly, it was thought that the greater
rigidity of the system may increase selectivity for one diene
geometry in the product formation.
Once all these substrates were in hand, they were subjected to
the reductive decomplexation conditions and the product diene
mixtures were futher hydrogenated to afford saturated 1,7-
alkanediols (Table 1). Where the leaving group was an acetate
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
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Table 1 Reagents and conditions: (a) Ac2O, DMAP, NEt3, CH2Cl2, 0 ЊC; (b) (i) TBSOTf, NEt3, CH2Cl2, 0 ЊC; (ii) MsCl, NEt3, CH2Cl2, 0 ЊC;
(c) (i) TBSOTf, NEt3, CH2Cl2, 0 ЊC; (ii) Ac2O, DMAP, NEt3, CH2Cl2, 0 ЊC; (d) TBSOTf, NEt3, CH2Cl2, 0 ЊC then Ac2O, DMAP; (e) CDI, DMAP,
CH2Cl2; (f ) (i) Li naphthalenide (10 eq.), THF, Ϫ78 ЊC to rt, MeOH; (ii) H2, Pd/C, EtOAc; (g) (i) Li naphthalenide (5 eq.), THF, Ϫ78 ЊC to rt; (ii) H2,
Pd/C, EtOAc
Decomplex- Diene
b, c
Protection
procedure
ation
geometry
Alcohol
Protected product
Yield procedure
(E,E) : (Z,E) : (E,Z) Decomplexed product
Yieldd
81
a
96
f
f
a
93
83
93
g
g
0.70 : 0.17 : 0.13
13a 14a 15a
a
91
0.53 : 0.19 : 0.28
91
13b 14b 15b
a
a
97
95
g
g
0.62 : 0.15 : 0.23
96
96
13c 14c 15c
0.26 : 0.67 : 0.07
13c 14c 15c
b
c
66a
75a
g
g
No isolable product
0.62 : 0.20 : 0.18
95
13d 14d 15d
d
e
76
72
g
g
89
96
0.74 : 0.26 : 0.00
13e 14e 15e
a Isolated yield for two steps via intermediate 6f. b Where recorded. c As determined by the 1H 600 MHz NMR spectra. d Isolated yield for two steps.
species is s-trans, 21c and 21d. For endo complexes, the former
seems to be the most significant and the major product is an
(E,E)-diene, corresponding to elimination from 21c. For an exo
complex the endo substituent is a proton and clash with the
carbonyl ligands becomes the more significant factor. This
results in 21b being favoured and the major product observed is
a (Z,E)-diene, 22b. There is no product corresponding to elim-
ination from 21a and this is probably due to the 1,3-allylic
strain of two s-cis bonds. (E,Z)-dienes are observed as a minor
component in all examples studied, except in the case of cyclic
carbonates. For this substrate, it is presumed that adoption of
the s-cis bond between the olefin and the leaving group results
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
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Scheme 3 Proposed mechanism for single electron reductive decomplexation.
in larger strain than in the case of the acetate, due to the greater
rigidity of the system, and this may account for no product,
22d, corresponding to this species, 21d, being observed.
follows: chemical shift, δ (ppm) [number of protons, multi-
plicity, coupling constant J (Hz), and assignment]. Residual
protic solvent CHCl3 (δH = 7.26 ppm) or C6H6 (δH = 7.20 ppm)
was used as the internal reference. 13C NMR spectra were
recorded in CDCl3 or C6D6 at 150 MHz or 100 MHz on Bruker
DRX-600 or DRX-400 or spectrometers, using the central res-
onance of CDCl3 (δC = 77.0 ppm) or C6D6 (δC = 128.0 ppm) as
the internal reference. In distortionless enhancement by polar-
isation transfer experiments (DEPT135) signals with an odd
number of protons attached are designated (Ϫ) and those with
an even number (ϩ). For those cases where an inseperable
mixture of compounds was produced, the data reported was
obtained on the mixture. Infra-red spectra were recorded on
Perkin-Elmer 983G, FTIR 1620 or Perkin Elmer ATR Spec-
trum 1 spectrometers. Mass spectra were obtained on Kratos
MS890MS, Bruker BIOAPEX 4.7 T FTICR or Micromass
Q-TOF spectrometers at the Department of Chemistry, Uni-
versity of Cambridge. The following ionisation techniques were
used: electron ionisation (EI), chemical ionisation (CI), fast
atom bombardment (FAB) and electrospray (ES). Optical
rotation measurements are reported in 10Ϫ1 deg cm2 gϪ1; con-
centrations (c) are in g 100 dmϪ3. Flash column chromatography
was carried out using Merck Kieselgel (230–400 mesh) unless
otherwise indicated. Analytical thin layer chromatography was
Conclusions
An extremely high yielding reductive decomplexation method
for π-allyltricarbonyliron lactone complexes has been
developed to afford stereodefined 1,7-alkanediols after hydro-
genation. The reaction affords a predictable diene geometry
with good selectivity, where endo complexes furnish (E,E)-
dienes and exo complexes (Z,E)-dienes. A mechanism that is
cosistent not only with these recent results but also our previous
understanding of these complexes has been proposed. Fur-
thermore, an array of densely functionalised lactone complexes
has been synthesised which have potential for natural product
synthesis.
Experimental
General experimental
1H NMR spectra were recorded in CDCl3 or C6D6 on Bruker
DRX-600 or DRX-400 spectrometers and are reported as
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
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performed using precoated glass-backed plates (Merck
Kieselgel 60 F254) and visualised by ultraviolet, acidic ammo-
nium molybdate() or acidic potassium permanganate solu-
tions. Aqueous solutions were saturated unless otherwise speci-
fied. Petrol refers to petroleum ether boiling point 40–60 ЊC. In
cases where mixtures of solvents were utilised, the ratios given
refer to the volumes used. All reactions were carried out under
an argon atmosphere in oven-dried glassware, which was cooled
under a continuous stream of argon immediately prior to use
unless otherwise stated. Et2O and THF were distilled from
sodium benzophenone ketyl. CH2Cl2 and PhMe were distilled
from calcium hydride.
solution of the dienol mixture in EtOAc (5 cm3). The mixture
was purged 5 times with H2 and stirred under an atmosphere
of H2. After 2 hours the mixture was filtered and concentrated
in vacuo to afford the reduced product without any further
purification.
Preparation of lithium naphthalenide solution
A suspension of naphthalene (6.5g, 50.7 mmol) and lithium
(1.15g, 50.0 mmol, ∼30 wt.% dispersion in mineral oil) in THF
(50 cm3) was sonicated for 30 min to yield a dark green solution
(∼1 mol dmϪ3).
The preparation of compounds 4a–d,10 5,6e4 and 7a,b6 is
described elsewhere.
F
lithium naphthalenide decomplexation. For a 0.20 mmol
scale reaction: to a solution of the acetate (1.0 eq.) in THF
(5 cm3) at Ϫ78 ЊC was added lithium naphthalenide (5.0 eq.)
and the reaction stirred at this temperature overnight. The mix-
ture was allowed to warm to room temperature and filtered
through a pad of silica. The residue was washed with Et2O
(50 cm3) and the filtrate concentrated in vacuo. The crude prod-
uct was purified by flash column chromatography to afford a
mixture of dienols.
General procedures
A
NaBH4 reduction. For a 0.50 mmol scale reaction: to a
solution of the ketone in CH2Cl2 (4 cm3) at Ϫ78 ЊC was added a
pre-cooled (Ϫ78 ЊC) solution of NaBH4 (10 eq.) in MeOH
(4 cm3) via cannula and the reaction stirred at this temperature
for 2 hours. A pre-cooled (Ϫ78 ЊC) solution of AcOH (2 cm3)
and THF (10 cm3) was added via canula, the mixture was
poured onto saturated aqueous NaHCO3 solution (40 cm3)
and extracted with Et2O (2 × 15 cm3). The combined organic
fractions were washed with brine and dried (MgSO4). Concen-
tration of the filtrate in vacuo followed by flash column
chromatography afforded the alcohol.
G
lithium naphthalenide decomplexation and reduction. For
a 0.20 mmol scale reaction: to a solution of the acetate (1.0 eq.)
in THF (5 cm3) at Ϫ78 ЊC was added lithium naphthalenide
(5.0 eq.) and the reaction was stirred at this temperature over-
night. The mixture was allowed to warm to room temperature
and filtered through a pad of silica. The residue was washed
with Et2O (50 cm3) and the filtrate concentrated in vacuo. The
crude product was purified by flash column chromatography to
afford a mixture of dienols. Pd/C (1.0 eq. by weight, 10 wt.% Pd
(dry basis) on activated carbon) was suspended in a solution of
the dienol mixture in EtOAc (5 cm3). The mixture was purged 5
times with H2 and stirred under an atmosphere of H2. After
2 hours the mixture was filtered and concentrated in vacuo to
afford the reduced product without any further purification.
B
acetate protection of alcohols. For a 0.5 mmol scale reac-
tion: to a solution of the alcohol (1.0 eq.), NEt3 (1.3 eq.) and
DMAP (0.1 eq.) in CH2Cl2 (5 cm3) at 0 ЊC was added Ac2O
(1.1 eq.). The reaction was allowed to warm to room temper-
ature, stirred for 2 hours, filtered through a pad of silica and
the residue washed with Et2O (50 cm3). Concentration of the
filtrate in vacuo afforded the acetate which was used without
further purification.
H
decomplexation, acetate cleavage and diene reduction. For
C
Al(i-Bu)3 reduction. For a 1.0 mmol scale reaction: to a
solution of the ketone (1.0 eq.) in CH2Cl2 (6 cm3) at 0 ЊC was
added Al(i-Bu)3 (2.0 eq., 1 mol dmϪ3 in PhMe) dropwise. After
30 min the solution was poured onto pre-cooled (0 ЊC) 1 mol
dmϪ3 aqueous HCl solution (30 cm3) and stirred vigourously for
20 min. CH2Cl2 (20 cm3) was added and the layers separated.
The aqueous layer was extracted with Et2O (30 cm3) and the
combined organic fractions were washed with brine and dried
(MgSO4). Concentration of the filtrate in vacuo followed by
flash column chromatography afforded the tertiary or second-
ary alcohol respectively.
a 0.20 mmol scale reaction: to a solution of the acetate (1.0
eq.) in THF (5 cm3) at Ϫ78 ЊC was added lithium naphthalenide
(10 eq.) and the reaction stirred at this temperature overnight.
The mixture was allowed to warm to room temperature, MeOH
(5 cm3) was added and the reaction was stirred for a further
2 hours before being filtered through a pad of silica. The resi-
due was washed with Et2O (50 cm3) and the filtrate was concen-
trated in vacuo. The crude product was purified by flash column
chromatography to afford a mixture of dienols. Pd/C (1.0 eq. by
weight, 10 wt.% Pd (dry basis) on activated carbon) was sus-
pended in a solution of the dienol mixture in EtOAc (5 cm3).
The mixture was purged 5 times with H2 and stirred under an
atmosphere of H2. After 2 hours the mixture was filtered and
concentrated in vacuo to afford the reduced product without
any further purification.
D
formation of cyclic carbonates. For a 0.30 mmol scale
reaction: to a solution of the alcohol and DMAP (0.1 eq.)
in CH2Cl2 (3 cm3) at room temperature was added CDI (3.0 eq.)
in one portion. After 1 hour the reaction mixture was puri-
fied directly by flash column chromatography to afford the
carbonate.
I
Pd/C catalysed reduction of dienes. For a 0.5 mmol scale
reaction: Pd/C (1.0 eq. by weight, 10 wt.% Pd (dry basis) on
activated carbon) was suspended in a solution of the alkene in
EtOAc (5 cm3). The mixture was purged 5 times with H2 and
stirred under an atmosphere of H2. After 2 hours the mixture
was filtered through a pad of Celite and the residue washed
with EtOAc (50 cm3). Concentration of the filtrate in vacuo
afforded the alkane which required no further purification.
E
cuprate decomplexation and diene reduction. For a 0.20
mmol scale reaction: to a suspension of CuI (5.0 eq.) in THF
(5 cm3) at Ϫ78 ЊC was added MeLi (10 eq., 1.4 mol dmϪ3 in
Et2O) dropwise. After complete addition the solution was
warmed to 0 ЊC and cooled back to Ϫ78 ЊC and then the alco-
hol (1.0 eq.) in THF (1 cm3) was added dropwise. The reaction
mixture was stirred at Ϫ78 ЊC overnight, allowed to warm to
room temperature, then poured onto NH4Cl solution and
extracted with Et2O (2 × 10 cm3). The combined organic frac-
tions were washed with brine and dried (MgSO4). Concen-
tration of the filtrate in vacuo followed by flash column chroma-
tography afforded a mixture of dienols. Pd/C (1.0 eq. by weight,
10 wt.% Pd (dry basis) on activated carbon) was suspended in a
Preparation and characterisation
(3E,2SR,5SR,6RS )-6-(Carbonyloxy-ꢁC)-2-hydroxy-(3,4,5-ꢂ)-
undec-3-en-5-yl]tricarbonyliron 2a. Iron lactone complex 2a
was prepared using general procedure A from [(3E,5SR,6RS)-
6-(carbonyloxy-κC)-2-oxo-(3,4,5-η)-undec-3-en-5-yl]tricarb-
onyliron8 (220 mg, 0.63 mmol) in CH2Cl2 (4 cm3) and NaBH4
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
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(240 mg, 6.3 mmol) in MeOH (4 cm3). After 1.5 hours THF–
AcOH work-up as described followed by flash column chrom-
atography (eluent – Et2O–petrol 1 : 1) afforded alcohol 2a as a
yellow gum (190 mg, 86%). Data were consistent with those
reported in the literature.8
1) afforded diol 6b as a solid (220 mg, 84%); νmax(soln:CH2Cl2)/
cmϪ1 3482 (OH), [2081, 2008 Fe(CO)] and 1662 (C᎐O); δ (400
᎐
H
MHz; CDCl3) 4.89 (1 H, dd, J 12.2 and 8.4, 8-H), 4.62 (1 H, dd,
J 8.4 and 4.6, 7-H), 4.54 (1 H, d, J 9.6, 10-H), 4.25 (1 H, q, J 7.1,
6-H), 4.18 (1 H, s, OH × 1), 3.98 (2 H, m, 9-H and 12-H), 1.99
(2 H, d, J 14.5, 11-HA and OH × 1), 1.77 (1 H, dt, J 14.5 and
10.2, 11-HB), 1.59–1.26 (9 H, m, 2-H × 2, 3-H × 2, 4-H × 2, 5-H
× 2 and 13-H), 0.98 (3 H, d, J 7.3, 13-CCH3), 0.97 (3 H, d, J 7.3,
14-H × 3) and 0.83 (3 H, t, J 6.8, 1-H × 3); δC(100 MHz; CDCl3)
209.7, 207.0, 207.0, 203.4, 87.9, 87.2, 77.2, 75.9, 73.3, 71.5, 45.0,
40.6, 36.7, 31.6, 26.6, 22.5, 18.3, 13.9 and 13.9; m/z(FAB) 425
(100%, MHϩ); [Found (MHϩ) 425.1262. C19H29FeO7 requires
MH, 425.1263].
[(3E,2SR,5SR,6RS )-2-Acetoxy-6-(carbonyloxy-ꢁC)-(3,4,5-
ꢂ)-undec-3-en-5-yl]tricarbonyliron 2b. Acetate 2b was prepared
according to general procedure B from iron lactone complex 2a
(130 mg, 0.37 mmol), NEt3 (49 mg, 0.48 mmol) and DMAP
(5 mg, 0.04 mmol) in CH2Cl2 (4 cm3) and Ac2O (41 mg, 0.41
mmol). Work-up as described above afforded acetate 2b as a
gum (134 mg, 92%); νmax(soln:CH2Cl2)/cmϪ1 [2083, 2027
Fe(CO)], 1737 (C᎐O) and 1664 (C᎐O); δ (400 MHz; CDCl );
᎐
᎐
H
3
5.38 (1 H, quin, J 6.1, 2-H), 4.63 (2 H, m, 4-H and 5-H), 4.26
(1 H, m, 6-H), 3.93 (1 H, dd, J 11.7 and 4.9, 3-H), 2.03 (3 H, s,
COCH3), 1.56 (3 H, d, J 6.5, 1-H × 3), 1.55–1.22 (8 H, m, 7-H ×
2, 8-H × 2, 9-H × 2 and 10-H × 2) and 0.88 (3 H, t, J 6.8, 11-H
× 3); δC(100 MHz; CDCl3) 208.7, 206.2, 204.3, 203.3, 170.1,
88.6, 82.6, 77.1, 70.7, 65.8, 36.6, 31.5, 26.6, 22.5, 20.8, 15.2 and
13.9; m/z(FAB) 395 (100%, MHϩ); [Found (MHϩ) 395.0816.
C17H23FeO7 requires MH, 395.0793].
[(4E,1RS,3SR,6SR,7RS )-7-(Carbonyloxy-ꢁC)-1-cyclohexyl-
1,3-dihydroxy-(4,5,6-ꢂ)-dodec-4-en-6-yl]tricarbonyliron 6c. Iron
lactone complex 6c was prepared using general procedure A
from ketone 4c (220 mg, 0.48 mmol) in CH2Cl2 (4 cm3) and
NaBH4 (180 mg, 4.8 mmol) in MeOH (4 cm3). After 5 hours
THF–AcOH work-up as described above followed by flash
column chromatography (eluent – Et2O–petrol 1 : 1 10 : 1)
afforded diol 6c as a solid (183 mg, 83%); νmax(soln:CH2Cl2)/
cmϪ1 3476 (OH), [2081, 2009 Fe(CO)] and 1662 (C᎐O); δ (400
᎐
H
Undecan-6-ol 3. Method 1: alcohol 3 was prepared according
to general procedure E from alcohol 2a (160 mg, 0.45 mmol) in
THF (2 cm3), CuI (433 mg, 2.3 mmol) in THF (8 cm3) and
MeLi (3.2 cm3, 4.5 mmol; 1.4 M in Et2O). Work-up as described
above followed by flash column chromatography (eluent –
Et2O–petrol 1 : 2 1 : 1) and reduction catalysed by Pd/C
(160 mg, 10 wt.% Pd (dry basis) on activated carbon) in EtOAc
(5 cm3) afforded the alkanol 3 (61 mg, 78%). The product was
identical to sample obtained from Lancaster.
Method 2: alcohol 3 was prepared according to general pro-
cedure G from acetate 2b (110 mg, 0.28 mmol) in THF (5 cm3)
and lithium naphthalenide (1.4 cm3, 1.4 mmol, 1 mol dmϪ3
solution in THF). Work-up as described followed by flash
column chromatography (eluent – Et2O–petrol 1 : 2 1 : 1) and
reduction catalysed by Pd/C (110 mg, 10 wt.% Pd (dry basis) on
activated carbon) in EtOAc (5 cm3) afforded the alkanol 3
(44 mg, 92%). The product was identical to sample obtained
from Lancaster.
MHz; CDCl3) 4.90 (1 H, dd, J 12.3 and 8.4, 5-H), 4.62 (1 H, dd,
J 8.4 and 4.6, 6-H), 4.52 (1 H, d, J 9.8, 3-H), 4.26 (2 H, m, 7-H
and OH × 1), 4.00 (1 H, dd, J 12.3 and 2.7, 4-H), 3.75 (1 H, ddd,
J 10.4, 5.2 and 1.4, 1-H), 1.99 (1 H, d, J 14.4, 2-HA), 1.93–0.97
(19 H, m, cyclohexyl × 9, 2-HB, 8-H × 2, 9-H × 2, 10-H × 2,
11-H × 2 and OH) and 0.82 (5 H, m, cyclohexyl × 2 and 12-H ×
3); δC(100 MHz; CDCl3) 209.7, 207.2, 206.6, 203.4, 88.0, 87.1,
77.1, 76.7, 75.9, 71.5, 44.6, 42.0, 41.3, 36.7, 31.6, 28.6, 27.7,
26.6, 26.0, 22.6, 22.5 and 13.9; m/z(FAB) 465 (100%, MHϩ);
[Found (MHϩ) 465.1590. C22H33FeO7 requires MH, 465.1576].
[(4E,1RS,3SR,6SR,7RS )-7-(Carbonyloxy-ꢁC)-1,3-di-
hydroxy-1-phenyl-(4,5,6-ꢂ)-dodec-4-en-6-yl]tricarbonyliron 6d.
Iron lactone complex 6d was prepared using general procedure
A from ketone 4d (190 mg, 0.42 mmol) in CH2Cl2 (3.5 cm3) and
NaBH4 (157 mg, 4.1 mmol) in MeOH (3.5 cm3). After 5 hours
THF–AcOH work-up as described followed by flash column
chromatography (eluent – Et2O–petrol 1 : 1 10 : 1) afforded
diol 6d as a solid (166 mg, 87%); νmax(soln:CH2Cl2)/cmϪ1 3500
[(8E,6RS,7SR,10SR,12SR)-6-(Carbonyloxy-ꢁC)-10,12-di-
hydroxy-(7,8,9-ꢂ)-heptadec-8-en-7-yl]tricarbonyliron 6a. Iron
lactone complex 6a was prepared using general procedure A
from ketone 4a (180 mg, 0.40 mmol) in CH2Cl2 (3.5 cm3) and
NaBH4 (150 mg, 4.0 mmol) in MeOH (3.5 cm3). After 2 hours
THF–AcOH work-up as described above followed by flash
column chromatography (eluent – Et2O–petrol 1 : 1 3 : 1)
afforded diol 6a as a solid (146 mg, 81%); νmax(soln:CH2Cl2)/
cmϪ1 3475 (OH), [2081, 2026 Fe(CO)] and 1662 (C᎐O); δ (400
MHz; CDCl3) 4.87 (1 H, dd, J 12.1 and 8.3, 8-H), 4.61 (1 H,
ddd, J 8.3, 4.7 and 0.5, 7-H), 4.51 (1 H, d, J 9.8, 10-H), 4.25 (1
H, m, 6-H), 3.97 (2 H, m, 9-H and 12-H), 1.93 (1 H, d, J 14.4,
11-HA), 1.75 (1 H, dt, J 14.4 and 10.2, 11-HB), 1.57–1.02 (18 H,
m, 2-H × 2, 3-H × 2, 4-H × 2, 5-H × 2, 13-H × 2, 14-H × 2,
15-H × 2, 16-H × 2 and OH × 2) and 0.90 (6 H, m, 1-H × 3 and
17-H × 3); δC(100 MHz; CDCl3) 209.7ϩ, 207.0ϩ, 207.0ϩ,
203.3ϩ, 87.9Ϫ, 87.2Ϫ, 77.3Ϫ, 75.9Ϫ, 73.6Ϫ, 71.5Ϫ, 45.0ϩ,
38.4ϩ, 36.7ϩ, 31.7ϩ, 31.6ϩ, 26.6ϩ, 24.8ϩ, 22.5ϩ, 22.5ϩ,
13.9Ϫ and 13.9Ϫ; m/z(FAB) 453 (60%, MHϩ) and 323 (100);
[Found (MHϩ) 453.1569. C21H33FeO7 requires MH, 453.1576].
(OH), [2081, 2007 Fe(CO)] and 1663 (C᎐O); δ (400 MHz;
᎐
H
CDCl3) 7.37–7.31 (5 H, m, C6H5), 5.02 (1 H, d, J 9.6, 1-H), 4.88
(1 H, dd, J 12.1 and 8.4, 5-H), 4.62 (2 H, m, 3-H and 6-H), 4.23
(1 H, q, J 5.1, 7-H), 4.13 (1 H, s, OH × 1), 3.96 (1 H, dd, J 12.1
and 3.0, 4-H), 2.62 (1 H, s, OH × 1), 2.12 (2 H, m, 2-H × 2),
1.62–1.27 (8 H, m, 8-H × 2, 9-H × 2, 10-H × 2 and 11-H × 2)
and 0.88 (3 H, t, J 6.8, 12-H × 3); δC(100 MHz; CDCl3) 209.5ϩ,
207.3ϩ, 206.8ϩ, 203.3ϩ, 143.7ϩ, 128.7Ϫ, 128.0ϩ, 125.6Ϫ,
87.5Ϫ, 87.4Ϫ, 77.1Ϫ, 76.1Ϫ, 75.6Ϫ, 71.4Ϫ, 47.1ϩ, 36.6ϩ,
31.6ϩ, 26.6ϩ, 22.5ϩ and 13.9Ϫ; m/z(FAB) 459 (100%, MHϩ);
[Found (MHϩ) 459.1104. C22H27FeO7 requires MH, 459.1106].
᎐
H
[(8E,6RS,7SR,10SR,12RS )-12-(tert-Butyl-dimethyl-silanyl-
oxy)-6-(carbonyloxy-ꢁC)-10-hydroxy-13-methyl-(7,8,9-ꢂ)-tetra-
dec-8-en-7-yl]tricarbonyliron 6f. To a solution of diol 6b (380
mg, 0.90 mmol) and NEt3 (110 mg, 1.1 mmol) in CH2Cl2 (5 cm3)
at 0 ЊC was added TBSOTf (260 mg, 0.98 mmol) dropwise.
After 2 hours the mixture was purified directly by flash column
chromatography (eluent – Et2O–petrol 1 : 9 1 : 2) to afford
TBS protected iron lactone 6f (396 mg, 82%); νmax(soln:CH2Cl2)/
cmϪ1 3474 (OH), [2080, 2006 Fe(CO)] and 1663 (C᎐O); δ (400
᎐
H
[(8E,6RS,7SR,10SR,12RS )-6-(Carbonyloxy-ꢁC)-10,12-di-
hydroxy-13-methyl-(7,8,9-ꢂ)-tetradec-8-en-7-yl]tricarbonyliron
6b. Iron lactone complex 6b was prepared using general pro-
cedure A from ketone 4b (260 mg, 0.62 mmol) in CH2Cl2
(4 cm3) and NaBH4 (232 mg, 6.2 mmol) in MeOH (4 cm3). After
2 hours THF–AcOH work-up as described above followed by
flash column chromatography (eluent – Et2O–petrol 1 : 1 3 :
MHz; CDCl3) 4.91 (1 H, dd, J 12.2 and 8.4, 8-H), 4.61 (1 H, dd,
J 8.4 and 4.5, 7-H), 4.48 (1 H, d, J 9.5, 10-H), 4.25 (1 H, q, J 5.2,
6-H), 4.04 (1 H, m, 12-H), 3.98 (1 H, dd, J 12.2 and 2.5, 9-H),
3.76 (1 H, s, OH), 2.00 (1 H, dt, J 14.3 and 2.5, 11-HA), 1.73
(1 H, dt, J 14.3 and 9.8, 11-HB), 1.65–1.15 (9 H, m, 2-H × 2, 3-H
× 2, 4-H × 2, 5-H × 2 and 13-H), 0.91 (18 H, m, 1-H × 3,
13-CCH3, 14-H × 3 and SiC(CH3)3), 0.14 (3 H, s, Si(CH3) × 1)
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3202

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and 0.13 (3 H, s, Si(CH3) × 1); δC(100 MHz; CDCl3) 209.8,
207.2, 206.5, 203.3, 88.0, 86.8, 77.2, 75.8, 74.0, 70.4, 45.0, 40.4,
36.7, 31.6, 26.6, 25.8, 22.5, 17.9, 17.6, 14.2, 13.9, Ϫ3.8 and
Ϫ4.8; m/z(ES) 539 (100%, MHϩ); [Found (MHϩ) 539.2144.
C25H43FeO7Si requires MH, 539.2127].
6-H), 3.90 (1 H, m, 9-H), 2.22–1.98 (2 H, m, 11-H × 2), 2.08
(3 H, s, COCH3 × 1), 2.07 (3 H, s, COCH3 × 1), 1.65–1.22 (16
H, m, 2-H × 2, 3-H × 2, 4-H × 2, 5-H × 2, 13-H × 2, 14-H × 2,
15-H × 2 and 16-H × 2) and 0.89 (6 H, t, J 6.8, 1-H × 3 and
17-H × 3); δC(100 MHz; CDCl3) 208.7ϩ, 206.2ϩ, 204.0ϩ,
202.8ϩ, 170.9ϩ, 170.0ϩ, 90.0Ϫ, 80.7Ϫ, 77.3Ϫ, 77.1Ϫ, 72.1Ϫ,
70.8Ϫ, 41.4ϩ, 36.5ϩ, 34.5ϩ, 31.5ϩ, 31.5ϩ, 26.5ϩ, 24.8ϩ,
22.5ϩ, 22.5ϩ, 21.1Ϫ, 20.7Ϫ, 13.9Ϫ and 13.9Ϫ; m/z(FAB) 537
(100%, MHϩ); [Found (MHϩ) 537.1801. C25H37FeO9 requires
MH, 537.1787].
[(6E,2R,4R,5S,8S )-4-(Carbonyloxy-ꢁC)-2,10-di(tert-butyl-
dimethyl-silanyloxy)-8-hydroxy-(5,6,7-ꢂ)-dec-6-en-5-yl]tri-
carbonyliron 7a. Iron lactone complex 7a was prepared using
general procedure C from [(6E,2R,4R,5S)-4-(carbonyloxy-κC)-
2,10-di(tert-butyl-dimethyl-silanyloxy)-8-oxo-(5,6,7-η)-dec-6-
en-5-yl]tricarbonyliron6 (280 mg, 0.47 mmol) in CH2Cl2 (4 cm3)
and Al(i-Bu)3 (1.0 cm3, 1.0 mmol; 1.0 mol dmϪ3 solution in
PhMe). Work-up as described followed by flash column chro-
matography (eluent – Et2O–petrol 1 : 3 1 : 1) afforded alcohol
7a as a solid (227 mg, 81%); [α]2D5 Ϫ99.6 (c 0.49 in CH2Cl2);
νmax(film)/cmϪ1 3432 (OH), [2082, 2024 (FeCO)] and 1640
[(8E,6RS,7SR,10SR,12RS )-(Carbonyloxy-ꢁC)-10,12-di-
acetoxy-13-methyl-(7,8,9-ꢂ)-tetradec-8-en-7-yl] tricarbonyliron
8b. Diacetate 8b was prepared using general procedure B from
iron lactone complex 6b (160 mg, 0.38 mmol), NEt3 (99 mg,
0.98 mmol) and DMAP (9 mg, 0.08 mmol) in CH2Cl2 (4 cm3)
and Ac2O (85 mg, 0.83 mmol). Work-up as described above
afforded diacetate 8b as a gum (178 mg, 93%); νmax(soln:CH2-
Cl2)/cmϪ1 [2084, 2017 Fe(CO)], 1736 (C᎐O) and 1667 (C᎐O);
(C᎐O); δ (600 MHz; C D ) 4.70 (1 H, dd, J 12.1 and 8.5, 6-H),
᎐
H
6
6
4.28 (2 H, m, 4-H and 8-H), 4.15 (1 H, d, J 12.1, 7-H), 4.07 (1 H,
m, 5-H), 4.03 (1 H, m, 2-H), 3.87 (1 H, s, OH × 1), 3.64 (1 H, m,
10-HA), 3.57 (1 H, m, 10-HB), 1.97 (1 H, ddd, J 13.6, 8.5 and
5.5, 3-HA), 1.91 (1 H, m, 9-HA), 1.65 (1 H, ddd, J 13.6, 6.8 and
5.1, 3-HB), 1.54 (1 H, d, J 14.1, 9-HB), 1.16 (3 H, d, J 6.0, 1-H ×
3), 1.06 (9 H, s, SiC(CH3)3 × 1), 0.96 (9 H, s, SiC(CH3)3 × 1),
0.16 (3 H, s, Si(CH3) × 1), 0.15 (3 H, s, Si(CH3) × 1), 0.06 (3 H,
s, Si(CH3) × 1) and 0.05 (3 H, s, Si(CH3) × 1); δC(150 MHz;
C6D6) [210.5, 207.7, 203.9, 202.2 Fe(CO) × 4], 88.1 (7-C), 87.1
(6-C), 76.2 (5-C), 73.9 (4-C), 71.1 (8-C), 66.6 (2-C), 62.6 (10-C),
46.8 (3-C), 40.7 (9-C), 25.8 (SiC(CH3)3 × 1), 25.6 (SiC(CH3)3 ×
1), 22.9 (1-C), 17.9 (SiC(CH3)3 × 1), 17.9 (SiC(CH3)3 × 1), Ϫ4.5
(Si(CH3) × 1), Ϫ4.9 (Si(CH3) × 1), Ϫ5.8 (Si(CH3) × 1) and Ϫ5.9
(Si(CH3) × 1); m/z(ES) 621 (15%, MNaϩ) and 509 (100); [Found
(MNaϩ) 621.1980. C26H46FeNaO8Si2 requires MNa, 621.1978].
᎐
᎐
δH(400 MHz; CDCl3) 5.19 (1 H, qd, J 6.0 and 1.2, 10-H), 5.06
(1 H, m, 12-H), 4.69 (1 H, m, 8-H), 4.68 (1 H, m, 7-H), 4.26
(1 H, m, 6-H), 3.90 (1 H, m, 9-H), 2.22–1.97 (2 H, m, 11-H × 2),
2.08 (3 H, s, COCH3 × 1), 2.07 (3 H, s, COCH3 × 1), 1.68–1.15
(9 H, m, 2-H × 2, 3-H × 2, 4-H × 2, 5-H × 2 and 13-H) and 0.83
(3 H, t, J 6.8, 1-H × 3, 13-CCH3 and 14-H × 3); δC(100 MHz;
CDCl3) 208.7, 206.2, 204.0, 202.8, 170.8, 170.0, 90.0, 80.7, 77.2,
77.1, 72.0, 70.5, 53.4, 41.5, 36.6, 31.5, 26.5, 22.4, 21.1, 20.7,
18.4, 13.9 and 13.7; m/z(FAB) 509 (75%, MHϩ), 511 (100);
[Found (MHϩ) 509.1476. C23H33FeO9 requires MH, 509.1474].
[(4E,1RS,3SR,6SR,7RS )-7-(Carbonyloxy-ꢁC)-1,3-di-
acetoxy-1-cyclohexyl-(4,5,6-ꢂ)-dodec-4-en-6-yl]tricarbonyliron
8c. Diacetate 8c was prepared using general procedure B from
iron lactone complex 6c (110 mg, 0.24 mmol), NEt3 (62 mg,
0.62 mmol) and DMAP (3 mg, 0.02 mmol) in CH2Cl2 (2.5 cm3)
and Ac2O (53 mg, 0.52 mmol). Work-up as described above
afforded diacetate 8c as a gum (118 mg, 91%); νmax(film)/cmϪ1
[(6E,2R,4R,5R,8R)-4-(Carbonyloxy-ꢁC)-2,10-di(tert-butyl-
dimethyl-silanyloxy)-8-hydroxy-(5,6,7-ꢂ)-dec-6-en-5-yl]tricarb-
onyliron 7b. Iron lactone complex 7b was prepared using
general procedure C from [(6E,2R,4R,5R)-4-(carbonyloxy-κC)-
2,10-di(tert-butyl-dimethyl-silanyloxy)-8-oxo-(5,6,7-η)-dec-6-
en-5-yl]tricarbonyliron6 (320 mg, 0.54 mmol) in CH2Cl2 (4.5
cm3) and Al(i-Bu)3 (1.1 cm3, 1.1 mmol; 1.0 mol dmϪ3 solution in
PhMe). Work-up as described followed by flash column chro-
matography (eluent – Et2O–petrol 1 : 3 1 : 1) afforded alcohol
7b as a solid (254 mg, 79%); [α]2D5 ϩ65.0 (c 0.36 in CH2Cl2);
νmax(film)/cmϪ1 3448 (OH), [2088, 2004 (FeCO)] and 1642
[2079, 2002 Fe(CO)], 1735 (C᎐O) and 1666 (C᎐O); δ (600
᎐
᎐
H
MHz; CDCl3) 5.07 (1 H, m, 3-H), 4.92 (1 H, m, 1-H), 4.77 (1 H,
dd, J 12.1 and 8.5, 5-H), 4.68 (1 H, dd, J 8.2 and 4.7, 6-H), 4.26
(1 H, m, 7-H), 3.87 (1 H, dd, J 12.1 and 6.5, 4-H), 2.08 (3 H, s,
COCH3 × 1), 2.07 (3 H, s, COCH3 × 1), 2.06 (2 H, m, 2-H × 2),
1.77–1.12 (17 H, m, cyclohexyl × 9, 8-H × 2, 9-H × 2, 10-H ×
2 and 11-H × 2), 1.02 (2 H, m, cyclohexyl × 2) and 0.88 (3 H, t,
J 6.8, 12-H × 3); δC(150 MHz; CDCl3) 208.7, 206.3, 204.0,
202.7, 171.1, 169.9, 90.4, 80.6, 77.2, 76.8, 74.2, 72.7, 41.8, 38.9,
36.5, 31.6, 28.8, 28.1, 26.4, 26.2, 26.0, 25.9, 22.4, 21.0, 20.8 and
13.9; m/z(ES) 571 (50%, MNaϩ) and 459 (100); [Found (MNaϩ)
571.1620. C26H36FeNaO9 requires MNa, 571.1606].
(C᎐O); δ (600 MHz; C D ) 4.81 (1 H, dd, J 11.8 and 8.2, 6-H),
᎐
H
6
6
4.26 (1 H, d, J 11.8, 7-H), 4.09 (1 H, t, J 7.1, 4-H), 4.04 (1 H,
sextet, J 6.1, 2-H), 3.96 (2 H, m, 5-H and 8-H), 3.90 (1 H, s, OH
× 1), 3.66 (1 H, m, 10-HA), 3.59 (1 H, m, 10-HB), 1.99 (1 H, ddd,
J 13.5, 8.6 and 5.6, 3-HA), 1.91 (1 H, m, 9-HA), 1.63 (1 H, m,
3-HB), 1.56 (1 H, d, J 14.0, 9-HB), 1.21 (3 H, d, J 6.1, 1-H × 3),
1.07 (9 H, s, SiC(CH3)3 × 1), 0.96 (9 H, s, SiC(CH3)3 × 1), 0.20
(3 H, s, Si(CH3) × 1), 0.16 (3 H, s, Si(CH3) × 1) and 0.06 (6 H, s,
Si(CH3) × 2); δC(150 MHz; C6D6) 210.9ϩ, 207.6ϩ, 204.2ϩ,
202.0ϩ, 88.4Ϫ, 87.6Ϫ, 75.3Ϫ, 71.5Ϫ, 71.0Ϫ, 66.2Ϫ, 62.6ϩ,
47.8ϩ, 40.5ϩ, 25.8Ϫ, 25.6Ϫ, 22.9Ϫ, 18.0ϩ, 17.9ϩ, Ϫ4.9Ϫ,
Ϫ4.9Ϫ, Ϫ5.8Ϫ and Ϫ5.9Ϫ; m/z(ES) 621 (10%, MNaϩ) and 509
(100); [Found (MNaϩ) 621.1954. C26H46FeNaO8Si2 requires
MNa, 621.1978].
[(6E,2R,4R,5S,8S )-8-Acetoxy-[2,10-di(tert-butyl-dimethyl-
silanyloxy)-4-(carbonyloxy-ꢁC)-(5,6,7-ꢂ)-dec-6-en-5-yl]tri-
carbonyliron 9a. Acetate 9a was prepared using general pro-
cedure B from iron lactone complex 7a (190 mg, 0.32 mmol),
NEt3 (84 mg, 0.84 mmol) and DMAP (4 mg, 0.03 mmol) in
CH2Cl2 (3 cm3) and Ac2O (36 mg, 0.35 mmol). Work-up as
described above afforded acetate 9a as a solid (197 mg, 97%);
[α]2D5 Ϫ126.5 (c 0.34 in CH2Cl2); νmax(film)/cmϪ1 [2082, 2010
Fe(CO)], 1741 (C᎐O) and 1668 (C᎐O); δ (600 MHz; C D ) 5.61
᎐
᎐
H
6
6
(1 H, m, 8-H), 4.30 (1 H, dd, J 12.2 and 8.4, 6-H), 4.23 (1 H,
quin, J 4.4, 4-H), 4.13 (1 H, d, J 12.2 and 5.7, 7-H), 4.01 (2 H,
m, 2-H and 5-H), 3.67 (1 H, m, 10-HA), 3.61 (1 H, m, 10-HB),
2.04 (1 H, m, 9-HA), 1.88 (1 H, ddd, J 13.6, 8.6 and 5.3, 3-HA),
1.82 (3 H, s, COCH3), 1.81 (1 H, m, 9-HB), 1.60 (1 H, ddd,
J 13.6, 6.9 and 4.9, 3-HB), 1.13 (3 H, d, J 6.1, 1-H × 3), 1.05
(18 H, s, SiC(CH3)3 × 2), 0.15 (3 H, s, Si(CH3) × 1), 0.14 (3 H, s,
Si(CH3) × 1) and 0.14 (6 H, s, Si(CH3) × 2); δC(150 MHz; C6D6)
[209.6, 207.1, 203.3, 199.9 Fe(CO) × 4], 169.2 (COCH3), 89.3
(6-C), 81.6 (7-C), 77.4 (5-C), 73.6 (4-C), 71.6 (8-C), 66.5 (2-C),
58.9 (10-C), 46.7 (3-C), 39.5 (9-C), 25.8 (SiC(CH3)3 × 1), 25.8
[(8E,6RS,7SR,10SR,12SR)-6-(Carbonyloxy-ꢁC)-10,12-di-
acetoxy-(7,8,9-ꢂ)-heptadec-8-en-7-yl]tricarbonyliron 8a. Di-
acetate 8a was prepared using general procedure B from iron
lactone complex 6a (149 mg, 0.33 mmol), NEt3 (87 mg, 0.86
mmol) and DMAP (8 mg, 0.07 mmol) in CH2Cl2 (3.5 cm3) and
Ac2O (74 mg, 0.73 mmol). Work-up as described above afforded
diacetate 8a as a gum (170 mg, 96%); νmax(soln:CH2Cl2)/cmϪ1
[2092, 2030 Fe(CO)], 1742 (C᎐O) and 1675 (C᎐O); δ (400
᎐
᎐
H
MHz; CDCl3) 5.19 (1 H, qd, J 6.0 and 1.2, 10-H), 5.04 (1 H, m,
12-H), 4.68 (1 H, m, 8-H), 4.67 (1 H, m, 7-H), 4.26 (1 H, m,
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3203

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(SiC(CH3)3 × 1), 22.8 (1-C), 20.0 (COCH3), 18.1 (SiC(CH3)3 ×
1), 18.0 (SiC(CH3)3 × 1), Ϫ4.5 (Si(CH3) × 1), Ϫ4.9 (Si(CH3) ×
1 and Ϫ5.7 Si(CH3) × 2); m/z(ES) 663 (95%, MNaϩ) and 551
(100); [Found (MNaϩ) 663.2065. C28H48FeNaO9Si2 requires
MNa, 663.2084].
Si(CH3) × 1) and 0.06 (3 H, s, Si(CH3) × 1); δC(150 MHz;
CDCl3) 208.8, 206.3, 204.0, 203.3, 170.0, 88.5, 81.7, 77.2, 76.6,
73.2, 71.5, 39.6, 36.7, 33.0, 31.5, 26.6, 25.8, 22.4, 20.7, 18.0,
17.6, 17.2, 13.9, Ϫ4.2 and Ϫ4.6; m/z(ES) 603 (65%, MNaϩ) and
491 (100); [Found (MNaϩ) 603.2040. C27H44FeNaO8Si requires
MNa, 603.2053].
[(6E,2R,4R,5R,8R)-8-Acetoxy-2,10-di(tert-butyl-dimethyl-
silanyloxy)-4-(carbonyloxy-ꢁC)-(5,6,7-ꢂ)-dec-6-en-5-yl]tri-
carbonyliron 9b. Acetate 9b was prepared according to general
procedure B from iron lactone complex 7b (230 mg, 0.38
mmol), NEt3 (51 mg, 0.50 mmol) and DMAP (4 mg, 0.03
mmol) in CH2Cl2 (4 cm3) and Ac2O (43 mg, 0.42 mmol). Work-
up as described above afforded acetate 9b as a solid (234 mg,
95%); [α]2D5 ϩ93.0 (c 0.30 in CH2Cl2); νmax(film)/cmϪ1 [2083, 2013
[(8E,6RS,7SR,10SR,12SR)-10-Acetoxy-12-(tert-butyl-di-
methyl-silanyloxy)-6-(carbonyloxy-ꢁC)-(7,8,9-ꢂ)-heptadec-8-en-
7-yl]tricarbonyliron 11b. To a solution of diol 6a (90 mg, 0.20
mmol), NEt3 (52 mg, 0.52 mmol) and DMAP (3 mg, 0.02
mmol) in CH2Cl2 (2 cm3) at 0 ЊC was added TBSOTf (58 mg,
0.22 mmol) dropwise and the reaction stirred for 2 hours before
Ac2O (22 mg, 0.22 mmol) was added dropwise. After 1 hour the
mixture was purified directly by flash column chromatography
(eluent – Et2O–petrol 1 : 9 1 : 2) to afford protected iron
lactone 11b (92 mg, 76%); νmax(soln:CH2Cl2)/cmϪ1 [2082, 2025
Fe(CO)], 1742 (C᎐O) and 1666 (C᎐O); δ (600 MHz; C D ) 5.60
᎐
᎐
H
6
6
(1 H, m, 8-H), 4.43 (1 H, dd, J 12.1 and 8.0, 6-H), 4.02 (2 H, m,
2-H and 4-H), 3.96 (1 H, dd, J 12.1 and 5.6, 7-H), 3.91 (1 H, d,
J 8.0, 5-H), 3.62 (1 H, m, 10-HA), 3.58 (1 H, m, 10-HB), 1.97
(2 H, m, 3-HA and 9-HA), 1.82 (3 H, s, COCH3), 1.80 (1 H, m,
9-HB), 1.56 (1 H, ddd, J 13.6, 7.2 and 5.5, 3-HB), 1.20 (3 H, d,
J 6.1, 1-H × 3), 1.07 (9 H, s, SiC(CH3)3 × 1), 1.05 (9 H, s,
SiC(CH3)3 × 1), 0.19 (3 H, s, Si(CH3) × 1), 0.14 (3 H, s, Si(CH3)
× 1), 0.14 (3 H, s, Si(CH3) × 1) and 0.14 (3 H, s, Si(CH3) × 1);
δC(150 MHz; C6D6) 210.1ϩ, 207.0ϩ, 203.7ϩ, 199.6ϩ, 169.2ϩ,
90.5Ϫ, 81.5Ϫ, 76.5Ϫ, 71.4Ϫ, 71.2Ϫ, 65.2Ϫ, 58.8ϩ, 47.8ϩ,
39.3ϩ, 25.8Ϫ, 25.8Ϫ, 22.8Ϫ, 20.0Ϫ, 18.1ϩ, 18.0ϩ, Ϫ4.7Ϫ,
Ϫ5.0Ϫ, Ϫ5.7Ϫ and Ϫ5.7Ϫ; m/z(ES) 663 (80%, MNaϩ) and 551
(100); [Found (MNaϩ) 663.2055. C28H48FeNaO9Si2 requires
MNa, 663.2084].
Fe(CO)], 1738 (C᎐O) and 1667 (C᎐O); δ (400 MHz; CDCl )
᎐
᎐
H
3
5.53 (1 H, q, J 4.8, 10-H), 4.63 (1 H, dd, J 8.3 and 4.3, 7-H),
4.58 (1 H, dd, J 12.0 and 8.3, 8-H), 4.24 (1 H, m, 6-H), 3.93
(1 H, dd, J 12.0 and 4.7, 9-H), 3.83 (1 H, quin, J 5.7, 12-H), 2.06
(1 H, m, 11-HA), 2.05 (3 H, s, COCH3), 1.92 (1 H, m, 11-HB),
1.68–1.20 (16 H, m, 2-H × 2, 3-H × 2, 4-H × 2, 5-H × 2, 13-H ×
2, 14-H × 2, 15-H × 2 and 16-H × 2) and 0.91 (15 H, m, 1-H ×
3, 17-H × 3 and SiC(CH3)3), 0.09 (3 H, s, Si(CH3) × 1) and 0.07
(3 H, s, Si(CH3) × 1); δC(100 MHz; CDCl3) 208.8, 206.3, 204.1
203.2, 170.0, 88.7, 81.8, 77.2, 71.4, 69.1, 67.4, 44.0, 37.2, 36.5,
31.9, 31.5, 26.6, 25.8, 25.6, 22.6, 22.4, 21.1, 18.0, 13.9, 13.9,
Ϫ4.0 and Ϫ4.5; m/z(ES) 631 (50%, MNaϩ), 609 (60, MHϩ) and
734 (100); [Found (MHϩ) 609.2588. C29H49FeO8Si requires
MH, 609.2546].
[(8E,6RS,7SR,10SR,12RS )-12-(tert-Butyl-dimethyl-silanyl-
oxy)-6-(carbonyloxy-ꢁC)-13-methyl-10-methyl
sulfonyloxy-
(7,8,9-ꢂ)-tetradec-8-en-7-yl]tricarbonyliron 10. To a solution of
alcohol 6f (110 mg, 0.20 mmol) and NEt3 (25 mg, 0.24 mmol) in
CH2Cl2 (5 cm3) at 0 ЊC was added methanesulfonyl chloride
(26 mg, 0.22 mmol) dropwise. After 2 hours the mixture was
purified directly by flash column chromatography (eluent –
Et2O–petrol 1 : 9 1 : 2) to afford iron lactone 10 (106 mg,
[(8E,6RS,7SR,10SR,12RS )-6-(Carbonyloxy-ꢁC)-10,12-di-
O-carbonate-13-methyl-(7,8,9-ꢂ)-tetradec-8-en-7-yl]tri-
carbonyliron 12a. Iron lactone complex 12a was prepared
according to general procedure D from diol 6b (120 mg, 0.28
mmol) and DMAP (4 mg, 0.03 mmol) in CH2Cl2 (2.5 cm3) and
CDI (136 mg, 0.84 mmol). Work-up as described above, flash
column chromatography (eluent – Et2O–petrol 1 : 1 Et2O)
afforded cyclic carbonate 12a as a solid (92 mg, 72%);
80%); νmax(film)/cmϪ1 [2082, 2003 Fe(CO)] and 1638 (C᎐O);
᎐
δH(600 MHz; CDCl3) 4.87 (1 H, dd, J 11.9 and 8.2, 8-H),
4.65 (1 H, dd, J 8.2 and 4.7, 7-H), 4.53 (1 H, d, J 9.7, 10-H),
4.25 (1 H, m, 6-H), 3.96 (1 H, dd, J 11.9 and 2.9, 9-H), 3.70
(1 H, m, 12-H), 2.14 (1 H, ddd, J 14.6, 4.2 and 2.0, 11-HA),
1.98 (1 H, octet, J 6.9, 13-H), 1.72 (1 H, ddd, J 14.6, 10.4
and 3.3, 11-HB), 1.55 (3 H, m, 4-HA and 5-H × 2), 1.54 (3 H,
s, SO2CH3), 1.41–1.26 (5 H, m, 2-H × 2, 3-H × 2 and 4-HB),
0.97 (3 H, d, J 6.7, 13-CCH3), 0.91 (12 H, m, 14-H × 3 and
SiC(CH3)3), 0.89 (3 H, t, J 6.7, 1-H × 3), 0.15 (3 H, s,
Si(CH3) × 1) and 0.12 (3 H, s, Si(CH3) × 1); δC(150 MHz;
CDCl3) 209.5, 206.8, 206.6, 203.6, 86.0, 77.4, 77.2, 76.8, 76.5,
67.8, 41.0, 36.7, 32.2, 31.5, 26.6, 25.9, 25.8, 22.5, 19.9, 18.3,
17.9, 13.9, Ϫ4.4 and Ϫ4.6; m/z(ES) 603 (65%, MNaϩ) and
491 (100); [Found (MNaϩ) 639.1715. C26H44FeNaO9SSi
requires MNa, 639.1722].
νmax(film)/cmϪ1 [2084, 2005 (FeCO)], 1750 (C᎐O) and 1663
᎐
(C᎐O); δ (600 MHz; CDCl ) 5.03 (1 H, dt, J 11.8 and 2.8,
᎐
H
3
10-H), 4.93 (1 H, dd, J 12.0 and 8.4, 8-H), 4.72 (1 H, dd, J 8.4
and 4.7, 7-H), 4.30 (2 H, m, 6-H and 12-H), 3.81 (1 H, dd,
J 12.0 and 2.8, 9-H), 2.35 (1 H, dd, J 14.2 and 3.0, 11-HA), 1.98
(1 H, m, 11-HB), 1.57 (1 H, m, 13-H), 1.49–1.24 (8 H, m, 2-H ×
2, 3-H × 2, 4-H × 2 and 5-H × 2), 1.05 (3 H, d, J 6.8, 14-H × 3),
1.02 (3 H, d, J 6.9, 13-CCH3) and 0.88 (3 H, t, J 6.9, 1-H × 3);
δC(150 MHz; CDCl3) 208.4, 206.1, 204.2, 201.4, 147.7, 87.9,
83.4, 78.1, 77.6, 77.1, 76.2, 53.4, 46.7, 32.3, 31.5, 26.6, 22.4,
17.2, 17.2 and 13.9; m/z(ES) 473 (40%, MNaϩ) and 349 (100);
[Found (MNaϩ) 473.0890. C20H26FeNaO8 requires MNa,
473.0875].
[(4E,1RS,3SR,6SR,7RS )-7-(Carbonyloxy-ꢁC)-1-cyclohexyl-
1,3-di-O-carbonate-(4,5,6-ꢂ)-dodec-4-en-6-yl]tricarbonyliron
12b. Iron lactone complex 12b was prepared using general pro-
cedure D from diol 6c (180 mg, 0.39 mmol) and DMAP (5 mg,
0.04 mmol) in CH2Cl2 (4 cm3) and CDI (189 mg, 1.2 mmol).
Work-up as described above, flash column chromatography
(eluent – Et2O–petrol 1 : 1 Et2O) afforded cyclic carbonate
12b as a solid (131 mg, 69%); νmax(soln:CH2Cl2)/cmϪ1 [2087 and
2017 Fe(CO)], 1754 (C᎐O) and 1668 (C᎐O); δ (400 MHz;
[(8E,6RS,7SR,10SR,12RS )-10-Acetoxy-12-(tert-butyl-di-
methyl-silanyloxy)-6-(carbonyloxy-ꢁC)-13-methyl-(7,8,9-ꢂ)-
tetradec-8-en-7-yl]tricarbonyliron 11a. Acetate 11a was pre-
pared according to general procedure B from iron lactone com-
plex 6f (115 mg, 0.21 mmol), NEt3 (28 mg, 0.28 mmol) and
DMAP (3 mg, 0.02 mmol) in CH2Cl2 (2 cm3) and Ac2O (24 mg,
0.24 mmol). Work-up as described above afforded acetate 11a
as a gum (113 mg, 91%); νmax(film)/cmϪ1 [2080, 2018 Fe(CO)],
᎐
᎐
H
1739 (C᎐O) and 1664 (C᎐O); δ (600 MHz; CDCl ) 5.55 (1 H,
CDCl3) 5.01 (1 H, dt, J 12.2 and 3.0, 3-H), 4.92 (1 H, dd, J 12.1
and 8.5, 5-H), 4.72 (1 H, dd, J 8.5 and 4.6, 6-H), 4.31 (2 H, m,
1-H and 7-H), 3.81 (1 H, dd, J 12.1 and 3.0, 4-H), 2.34 (1 H, dt,
J 14.3 and 3.0, 2-HA), 1.96 (2 H, m, 1-HЈ and 2-HB), 1.85–1.04
(16 H, m, cyclohexyl × 8, 8-H × 2, 9-H × 2, 10-H × 2 and 11-H
× 2) and 0.89 (5 H, m, cyclohexyl × 2 and 12-H × 3); δC(100
MHz; CDCl3) 208.5, 206.1, 204.2, 201.5, 88.0, 83.0, 78.0, 77.5,
᎐
᎐
H
3
m, 10-H), 4.65 (1 H, dd, J 8.3 and 4.6, 7-H), 4.58 (1 H, dd,
J 12.1 and 8.3, 8-H), 4.25 (1 H, m, 6-H), 3.93 (1 H, dd, J 12.1
and 4.3, 9-H), 3.67 (1 H, m, 12-H), 2.06 (3 H, s, COCH3), 1.99
(1 H, quin, J 6.9, 11-HA), 1.84 (2 H, m, 11-HB and 13-H), 1.60–
1.27 (8 H, m, 2-H × 2, 3-H × 2, 4-H × 2 and 5-H × 2), 0.88 (18
H, m, 1-H × 3, 13-CCH3, 14-H × 3 and SiC(CH3)3), 0.07 (3 H, s,
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3204

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77.0, 76.3, 41.9, 36.7, 31.8, 31.5, 27.7, 27.6, 26.6, 26.1, 25.3,
25.2, 22.4 and 13.9; m/z(FAB) 491 (100%, MHϩ); [Found
(MHϩ) 491.1363. C23H31FeO8 requires MH, 491.1368].
(1.00 H, m, 8-H × 0.19 and 9-H × 0.81), 5.70 (0.28 H, dd,
J 15.1 and 6.7, 7-H × 0.28), 5.64 (0.19 H, quin, J 7.5,
10-H × 0.19), 5.60 (1.06 H, dd, J 15.2 and 7.1, 7-H × 0.53 and
10-H × 0.53), 5.40 (0.28 H, m, 10-H × 0.28), 5.31 (0.19 H, t,
J 9.8, 7-H × 0.19), 4.76 (1.00 H, m, 12-H × 1.00), 4.55 (0.19 H,
m, 6-H × 0.19), 4.17 (0.28 H, d, J 5.3, 6-H × 0.28), 4.11 (0.53 H,
d, J 5.6, 6-H × 0.53), 2.46–2.29 (3.00 H, m, 11-H × 2.00 and
1-HЈ × 1.00), 2.02 (3.00 H, m, COCH3), 1.74–1.12 (16.00 H, m,
cyclohexyl × 8, 2-H × 2, 3-H × 2, 4-H × 2 and 5-H × 2), 1.02
(2.00 H, m, cyclohexyl × 2.00) and 0.88 (3 H, m, 1-H × 3.00);
δC(150 MHz; CDCl3) 170.8, 134.6, 132.1, 130.4, 129.8, 77.1,
72.7, 40.8, 37.3, 34.8, 31.7, 29.0, 28.1, 26.3, 26.0, 25.0, 22.6,
21.1, 21.1 and 14.0; m/z(EI) 304 (5%, Mϩ Ϫ H2O) and 69 (100);
[Found (Mϩ Ϫ H2O) 304.2416. C20H32O2 requires M Ϫ H2O,
304.2402].
[(4E,1RS,3SR,6SR,7RS )-7-(Carbonyloxy-ꢁC)-1,3-di-O-car-
bonate-1-phenyl-(4,5,6-ꢂ)-dodec-4-en-6-yl]tricarbonyliron 12c.
Iron lactone complex 12c was prepared using general procedure
D from diol 6d (153 mg, 0.33 mmol) and DMAP (4 mg, 0.03
mmol) in CH2Cl2 (3.5 cm3) and CDI (162 mg, 1.0 mmol). Work-
up as described above, flash column chromatography (eluent –
Et2O–petrol 1 : 1 Et2O) afforded cyclic carbonate 12c as a
solid (119 mg, 74%); νmax(soln:CH2Cl2)/cmϪ1 [2087 and 2016
Fe(CO)], 1760 (C᎐O) and 1659 (C᎐O); δ (400 MHz; CDCl )
᎐
᎐
H
3
7.43–7.35 (5 H, m, C6H5), 5.52 (1 H, dd, J 11.8 and 2.9, 1-H),
5.18 (1 H, dt, J 11.8 and 3.1, 3-H), 4.96 (1 H, dd, J 12.1 and 8.4,
5-H), 4.75 (1 H, dd, J 8.4 and 4.3, 6-H), 4.29 (1 H, q, J 6.5, 7-H),
3.83 (1 H, dd, J 12.1 and 3.0, 4-H), 2.63 (1 H, dt, J 14.5 and 3.1,
2-HA), 2.12 (1 H, dt, J 14.5 and 11.9, 2-HB), 1.62–1.27 (8 H, m,
8-H × 2, 9-H × 2, 10-H × 2 and 11-H × 2) and 0.88 (3 H, t,
J 6.8, 12-H × 3); δC(100 MHz; CDCl3) 208.4ϩ, 205.9ϩ, 203.8ϩ,
201.5ϩ, 147.3ϩ, 136.8ϩ, 129.4Ϫ, 129.0ϩ, 125.8Ϫ, 88.3Ϫ,
79.8Ϫ, 77.9Ϫ, 77.4Ϫ, 77.2Ϫ, 77.1Ϫ, 36.7ϩ, 36.7ϩ, 31.5ϩ,
26.6ϩ, 22.4ϩ and 13.9Ϫ; m/z(ES) 507 (55%, MNaϩ) and 734
(100); [Found (MNaϩ) 507.0734. C23H24FeNaO8 requires MNa,
507.0718].
(5E,7E,2R,4R)-2,10-Di(tert-butyl-dimethyl-silanyloxy)-4-
hydroxy-deca-5,7-diene 13c (5Z,7E,2R,4R)-2,10-Di(tert-butyl-
dimethyl-silanyloxy)-4-hydroxy-deca-5,7-diene 14c and (5E,
7Z,2R,4R)-2,10-Di(tert-butyl-dimethyl-silanyloxy)-4-hydroxy-
deca-5,7-diene 15c. Method 1: dienes 13c, 14c and 15c were
prepared according to general procedure F from iron lactone
complex 7a (140 mg, 0.22 mmol) in THF (5 cm3) and lithium
naphthalenide (1.1 cm3, 1.1 mmol, 1 mol dmϪ3 solution in
THF). Work-up as described above followed by flash column
chromatography (eluent – Et2O–petrol 1 : 3 1 : 1) afforded an
inseparable mixture of dienes 13c, 14c and 15c (0.62 : 0.15 :
0.23) as an oil (87 mg, 96%); νmax(film)/cmϪ1 3432 (OH); δH(600
MHz; CDCl3) 6.53 (0.23 H, dd, J 15.1 and 11.1, 6-H × 0.23),
6.39 (0.15 H, dd, J 14.7 and 11.8, 7-H × 0.15), 6.21 (0.62 H, dd,
J 15.1 and 10.6, 6-H × 0.62), 6.06 (0.85 H, dd, J 15.3 and 10.6,
7-H × 0.85), 5.97 (0.15 H, t, J 11.0, 6-H × 0.15), 5.71 (0.15 H,
m, 8-H × 0.15), 5.67 (0.85 H, m, 5-H × 0.23 and 8-H × 0.62),
5.57 (0.62 H, dd, J 15.1 and 6.2, 5-H × 0.62), 5.45 (0.23 H, m,
8-H × 0.23), 5.32 (0.15 H, dd, J 10.4 and 9.0, 5-H × 0.15), 4.72
(0.15 H, m, 4-H × 0.15), 4.35 (0.23 H, m, 4-H × 0.23), 4.31 (0.62
H, m, 4-H × 0.62), 4.08 (1.00 H, m, 2-H × 1.00), 3.63 (2.00 H,
m, 10-H × 2.00), 2.41 (0.46 H, m, 9-H × 0.46), 2.30 (1.54 H, m,
9-H × 1.54), 1.69–1.58 (2.00 H, m, 3-H × 2.00), 1.19 (3.00 H, m,
1-H × 3.00), 0.90 (18.00 H, m, SiC(CH3)3), 0.11 (6.00 H, m,
Si(CH3) × 2) and 0.04 (6.00 H, m, Si(CH3) × 2); δC(150 MHz;
CDCl3) 133.8, 131.4, 130.9, 129.9, 71.6, 69.2, 62.8, 46.3, 36.2,
25.9, 25.8, 24.5, 18.3, 17.9, Ϫ3.9, Ϫ4.8, Ϫ5.3 and Ϫ5.3; m/z(ES)
437 (100%, MNaϩ); [Found (MNaϩ) 437.2870. C22H46NaO3Si2
requires MNa, 437.2883].
Method 2: dienes 13c, 14c and 15c were prepared according
to general procedure F from iron lactone complex 7b (160 mg,
0.25 mmol) in THF (5 cm3) and lithium naphthalenide (1.3 cm3,
1.3 mmol, 1 mol dmϪ3 solution in THF]). Work-up as described
above followed by flash column chromatography (eluent –
Et2O–petrol 1 : 3 1 : 1) afforded an inseparable mixture of
dienes 13c, 14c and 15c (0.26 : 0.67 : 0.07) as an oil (102 mg,
98%); νmax(film)/cmϪ1 3431 (OH); δH(600 MHz; CDCl3) 6.53
(0.07 H, dd, J 15.1 and 11.1, 6-H × 0.07), 6.39 (0.67 H, dd,
J 14.7 and 11.8, 7-H × 0.67), 6.21 (0.26 H, dd, J 15.1 and 10.6,
6-H × 0.26), 6.06 (0.33 H, dd, J 15.3 and 10.6, 7-H × 0.33), 5.97
(0.67 H, t, J 11.0, 6-H × 0.67), 5.71 (0.67 H, m, 8-H × 0.67),
5.67 (0.33 H, m, 5-H × 0.07 and 8-H × 0.26), 5.57 (0.26 H, dd,
J 15.1 and 6.2, 5-H × 0.26), 5.45 (0.07 H, m, 8-H × 0.07), 5.32
(0.67 H, dd, J 10.4 and 9.0, 5-H × 0.67), 4.72 (0.67 H, m, 4-H ×
0.67), 4.35 (0.07 H, m, 4-H × 0.07), 4.31 (0.26 H, m, 4-H ×
0.26), 4.08 (1.00 H, m, 2-H × 1.00), 3.63 (2.00 H, m, 10-H ×
2.00), 2.41 (0.14 H, m, 9-H × 0.14), 2.30 (1.86 H, m, 9-H ×
1.86), 1.69–1.58 (2.00 H, m, 3-H × 2.00), 1.19 (3.00 H, m, 1-H ×
3.00), 0.90 (18.00 H, m, SiC(CH3)3), 0.11 (6.00 H, m, Si(CH3) ×
2) and 0.04 (6.00 H, m, Si(CH3) × 2); δC(150 MHz; CDCl3)
132.8, 131.9, 129.5, 127.1, 69.3, 67.5, 62.7, 46.3, 36.4, 25.9, 25.8,
24.5, 18.3, 17.9, Ϫ3.9, Ϫ4.8, Ϫ5.3 and Ϫ5.3; m/z(ES) 437
(100%, MNaϩ); [Found (MNaϩ) 437.2869. C22H46NaO3Si2
requires MNa, 437.2883].
(7E,9E,6RS,12RS )-12-Acetoxy-6-hydroxy-11-methyl-tetra-
deca-7,9-diene 13a (7Z,9E,6RS,12RS )-12-Acetoxy-6-hydroxy-
11-methyl-tetradeca-7,9-diene 14a and (7E,9Z,6RS,12RS )-12-
Acetoxy-6-hydroxy-11-methyl-tetradeca-7,9-diene 15a. Dienes
13a, 14a and 15a were prepared using general procedure F from
iron lactone complex 8b (140 mg, 0.28 mmol) in THF (6 cm3)
and lithium naphthalenide (1.4 cm3, 1.4 mmol, 1 mol dmϪ3
solution in THF). Work-up as described above followed by
flash column chromatography (eluent – Et2O–petrol 1 : 3 1 :
1) afforded an inseparable mixture of dienes 13a, 14a and 15a
(0.70 : 0.17 : 0.13) as an oil (73 mg, 94%); νmax(film)/cmϪ1 3379
(OH) and 1732 (C᎐O); δ (600 MHz; CDCl ) 6.47 (0.13 H,
᎐
H
3
dd, J 14.9 and 11.2, 8-H × 0.13), 6.36 (0.17 H, dd, J 14.5 and
11.7, 9-H × 0.17), 6.16 (0.70 H, dd, J 15.0 and 10.5, 8-H ×
0.70), 6.06 (0.87 H, dd, J 15.0 and 10.5, 8-H × 0.17 and 9-H
× 0.70), 6.01 (0.13 H, m, 9-H × 0.13), 5.70 (0.13 H, dd,
J 15.0 and 10.5, 7-H × 0.13), 5.60 (1.57 H, dd, J 15.0 and
7.0, 7-H × 0.70 and 10-H × 0.87), 5.40 (0.13 H, m, 10-H ×
0.13), 5.31 (0.17 H, m, 7-H × 0.17), 4.75 (1.00 H, m, 12-H ×
1.00), 4.55 (0.17 H, m, 6-H × 0.17), 4.17 (0.13 H, d, J 5.7,
6-H × 0.13), 4.11 (0.70 H, d, J 5.8, 6-H × 0.70), 2.38–2.29 (2.00
H, m, 11-H × 2.00), 2.03 (3.00 H, m, COCH3), 1.83 (1.00 H,
m, 13-H × 1.00), 1.58–1.25 (8.00 H, m, 2-H × 2.00, 3-H ×
2.00, 4-H × 2.00 and 5-H × 2.00) and 0.89 (9.00 H, m, 1-H ×
3.00, 13-CCH3 and 14-H × 3.00); δC(150 MHz; CDCl3) 170.8,
134.7, 132.1, 130.4, 129.8, 77.8, 72.7, 37.3, 34.7, 31.7, 30.9,
25.0, 22.6, 21.1, 18.6, 17.5 and 14.0; m/z(EI) 264 (5%, Mϩ
Ϫ
H2O) and 99 (100); [Found (Mϩ Ϫ H2O) 264.2081. C17H28O2
requires M Ϫ H2O, 264.2089].
(7E,9E,6RS,12RS )-12-Acetoxy-12-cyclohexyl-6-hydroxy-
dodeca-7,9-diene 13b (7Z,9E,6RS,12RS )-12-Acetoxy-12-cyclo-
hexyl-6-hydroxy-dodeca-7,9-diene 14b and (7E,9Z,6RS,12RS )-
12-Acetoxy-12-cyclohexyl-6-hydroxy-dodeca-7,9-diene
15b.
Dienes 13b, 14b and 15b were prepared using general procedure
F from iron lactone complex 8c (80 mg, 0.15 mmol) in THF
(4 cm3) and lithium naphthalenide (0.73 cm3, 0.73 mmol, 1 mol
dmϪ3 solution in THF). Work-up as described above followed
by flash column chromatography (eluent – Et2O–petrol 1 : 3
1
: 1) afforded an inseparable mixture of dienes 13b, 14b and 15b
(0.53 : 0.19 : 0.28) as an oil (43 mg, 92%); νmax(film)/cmϪ1 3455
(OH) and 1734 (C᎐O); δ (600 MHz; CDCl ) 6.46 (0.28 H, dd,
᎐
H
3
J 15.1 and 11.2, 8-H × 0.28), 6.35 (0.19 H, dd, J 14.7 and 11.7,
9-H × 0.19), 6.16 (0.53 H, dd, J 15.2 and 10.4, 8-H × 0.53), 6.04
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3205

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(7E,9E,6RS,12RS )-12-(tert-Butyl-dimethyl-silanyloxy)-6-
hydroxy-11-methyl-tetradeca-7,9-diene 13d (7Z,9E,6RS,12RS )-
12-(tert-Butyl-dimethyl-silanyloxy)-6-hydroxy-11-methyl-tetra-
deca-7,9-diene 14d and (7E,9Z,6RS,12RS )-12-(tert-Butyl-di-
methyl-silanyloxy)-6-hydroxy-11-methyl-tetradeca-7,9-diene
15d. Dienes 13d, 14d and 15d were prepared using general pro-
cedure F from iron lactone complex 11a (85 mg, 0.15 mmol) in
THF (4 cm3) and lithium naphthalenide (0.73 cm3, 0.73 mmol,
1 mol dmϪ3 solution in THF). Work-up as described above fol-
lowed by flash column chromatography (eluent – Et2O–petrol
1 : 3 1 : 1) afforded an inseparable mixture of dienes 13d, 14d
and 15d (0.62 : 0.20 : 0.18) as an oil (50 mg, 96%); νmax(film)/
cmϪ1 3344 (OH); δH(600 MHz; CDCl3) 6.47 (0.18 H, dd, J 15.1
and 11.1, 8-H × 0.18), 6.33 (0.20 H, dd, J 15.0 and 11.6, 9-H ×
0.20), 6.17 (0.62 H, dd, J 15.2 and 10.4, 8-H × 0.62), 6.03 (1.00
H, m, 8-H × 0.20 and 9-H × 0.80), 5.70 (1.00 H, m, 7-H × 0.18
and 10-H × 0.82), 5.58 (0.62 H, dd, J 15.2 and 6.9, 7-H × 0.62),
5.49 (0.18 H, m, 10-H × 0.18), 5.29 (0.20 H, m, 7-H × 0.20),
4.57 (0.20 H, m, 6-H × 0.20), 4.12 (0.80 H, m, 6-H × 0.80), 3.48
(1.00 H, m, 12-H × 1.00), 2.30–2.20 (2.00 H, m, 11-H × 2.00),
1.61 (1.00 H, m, 13-H × 1.00), 1.57–1.29 (8.00 H, m, 2-H ×
2.00, 3-H × 2.00, 4-H × 2.00 and 5-H × 2.00), 0.87 (18.00 H, m,
1-H × 3.00, 13-CCH3, 14-H × 3.00 and SiC(CH3)3) and 0.03
(6.00 H, s, Si(CH3) × 2.00); δC(150 MHz; CDCl3) 133.9, 131.9,
131.3, 130.8, 76.7, 72.8, 37.4, 37.3, 32.7, 31.7, 25.9, 25.0, 22.6,
18.5, 18.1, 17.3, 14.0, Ϫ4.2 and Ϫ4.6; m/z(EI) 354 (3%, Mϩ) and
73 (100); [Found (Mϩ) 354.2937. C21H42O2Si requires M,
354.2954].
(3RS,9RS )-3,9-Dihydroxy-2-methyl-tetradecane
16b.
Method 1: alcohol 16b was prepared according to general pro-
cedure H from acetate 8b (90 mg, 0.18 mmol) in THF (5 cm3),
lithium naphthalenide (1.8 cm3, 1.8 mmol, 1 mol dmϪ3 solution
in THF) and MeOH (5 cm3). Work-up as described above fol-
lowed by flash column chromatography (eluent – Et2O–petrol
1 : 1) and reduction catalysed by Pd/C (100 mg, 10 wt.% Pd (dry
basis) on activated carbon) in EtOAc (5 cm3) afforded alkanol
16b (36 mg, 83%); νmax(soln:CH2Cl2)/cmϪ1 3602 (OH); δH(400
MHz; CDCl3) 3.60 (2 H, m, 3-H and 9-H), 1.56–1.28 (21 H, m,
2-H, 4-H × 2, 5-H × 2, 6-H × 2, 7-H × 2, 8-H × 2, 10-H × 2,
11-H × 2, 12-H × 2, 13-H × 2 and OH × 2) and 0.91 (9 H, m,
1-H × 3, 2-CCH3 and 17-H × 3); δC(100 MHz; CDCl3) 72.0,
71.7, 39.7, 37.5, 37.4, 37.4, 31.9, 30.2, 29.7, 25.6, 25.3, 22.6,
18.8, 14.1 and 14.0; m/z(FAB) 245 (10%, MHϩ), 137 (100);
[Found (MHϩ) 245.2478. C15H33O2 requires MH, 245.2480].
Method 2: alcohol 16b was prepared according to general
procedure I from diene mixture 13e and 14e (0.74 : 0.26) (32 mg,
0.13 mmol) with Pd/C (30 mg, 10 wt.% Pd (dry basis) on activ-
ated carbon) in EtOAc (1 cm3). After 2 hours work-up as
described afforded alkanol 16b as an oil (33 mg, 100%). Data
were consistent with those reported (vide supra).
(3RS,9RS )-3-Acetoxy-9-hydroxy-2-methyl-tetradecane 17a.
Alcohol 17a was prepared according to general procedure I
from diene mixture 13a, 14a and 15a (0.70 : 0.17 : 0.13) (25 mg,
0.09 mmol) with Pd/C (25 mg, 10 wt.% Pd (dry basis) on activ-
ated carbon) in EtOAc (1 cm3). After 2 hours work-up as
described above afforded alkanol 17a as an oil (25 mg, 99%);
νmax(film)/cmϪ1 3468 (OH) and 1733 (C᎐O); δ (600 MHz;
(7E,9E,6RS,12RS )-6,12-Dihydroxy-12-methyl-tetradeca-
7,9-diene and (7Z,9E,6RS,12RS )-6,12-Dihydroxy-12-methyl-
tetradeca-7,9-diene. Dienes 13e and 14e were prepared using
general procedure F from iron lactone complex 12a (80 mg,
0.18 mmol) in THF (5 cm3) and lithium naphthalenide (0.89
cm3, 0.89 mmol, 1 mol dmϪ3 solution in THF). Work-up as
described above followed by flash column chromatography
(eluent – Et2O–petrol 1 : 1) afforded an inseparable mixture of
dienes 13e and 14e (0.74 : 0.26) as an oil (41 mg, 96%);
νmax(film)/cmϪ1 3451 (OH); δH(600 MHz; CDCl3) 6.44 (0.26 H,
dd, J 14.6 and 11.6, 9-H × 0.26), 6.20 (0.74 H, dd, J 14.9 and
10.4, 8-H × 0.74), 6.13 (0.74 H, dd, J 14.9 and 10.4, 9-H × 0.74),
6.05 (0.26 H, t, J 11.0, 8-H × 0.26), 5.77 (0.26 H, quin, J 7.5, 10-
H × 0.26), 5.71 (0.74 H, quin, J 7.4, 10-H × 0.74), 5.62 (0.74 H,
dd, J 14.9 and 6.9, 7-H × 0.74), 5.33 (0.26 H, t, J 9.9, 7-H ×
0.26), 4.57 (0.26 H, m, 6-H × 0.26), 4.12 (0.74 H, m, 6-H ×
0.74), 3.40 (1.00 H, m, 12-H × 1.00), 2.33 (1.00 H, m, 11-HA ×
1.00), 2.17 (1.00 H, m, 11-HB × 1.00), 1.69 (1.00 H, m, 13-H ×
1.00), 1.58–1.28 (8.00 H, m, 2-H × 2.00, 3-H × 2.00, 4-H × 2.00
and 5-H × 2.00) and 0.92 (9.00 H, m, 1-H × 3.00, 13-CCH3 and
14-H × 3.00); δC(150 MHz; CDCl3) 134.8, 132.6, 130.9, 130.3,
75.8, 72.7, 37.6, 37.3, 33.1, 31.7, 25.1, 22.6, 18.7, 17.4 and 14.0;
᎐
H
CDCl3) 4.73 (1 H, m, 3-H), 3.58 (1 H, m, 9-H), 2.04 (3 H, s,
COCH3), 1.80 (1 H, m, 2-H), 1.56–1.22 (19 H, m, 4-H × 2, 5-H
× 2, 6-H × 2, 7-H × 2, 8-H × 2, 10-H × 2, 11-H × 2, 12-H × 2,
13-H × 2 and OH) and 0.89 (9 H, m, 1-H × 3, 2-CCH3 and 14-H
× 3); δC(150 MHz; CDCl3) 171.0, 78.4, 71.9, 37.5, 37.4, 31.9,
31.4, 31.0, 29.6, 29.5, 25.5, 25.3, 22.6, 21.1, 18.5, 17.5 and 14.0;
m/z (EI) 268 (5%, Mϩ Ϫ H2O) and 69 (100); [Found (Mϩ
H2O) 268.2386. C17H32O2 requires M Ϫ H2O, 268.2402].
Ϫ
(1RS,7RS )-1-Acetoxy-1-cyclohexyl-7-hydroxy-dodecane 17b.
Alcohol 17b was prepared according to general procedure I
from diene mixture 13b, 14b and 15b (0.53 : 0.19 : 0.28) (38 mg,
0.12 mmol) with Pd/C (38 mg, 10 wt.% Pd (dry basis) on activ-
ated carbon) in EtOAc (1 cm3). After 2 hours work-up as
described afforded alkanol 17b as an oil (38 mg, 99%); νmax
-
(film)/cmϪ1 3430 (OH) and 1736 (C᎐O); δ (600 MHz; CDCl )
᎐
H
3
4.73 (1 H, m, 1-H), 3.58 (1 H, m, 7-H), 2.04 (3 H, s, COCH3),
1.74–1.22 (28 H, m, cyclohexyl × 9, 2-H × 2, 3-H × 2, 4-H × 2,
5-H × 2, 6-H × 2, 8-H × 2, 9-H × 2, 10-H × 2, 11-H × 2 and
OH), 1.00 (2 H, m, cyclohexyl × 2) and 0.89 (3 H, t, J 6.9, 12-H
× 3); δC(150 MHz; CDCl3) 171.0, 78.0, 71.9, 41.2, 37.5, 37.4,
31.9, 31.0, 29.5, 29.0, 28.0, 26.4, 26.1, 26.0, 25.5, 25.4, 25.3,
22.6, 21.1 and 14.1; m/z (ES) 349 (40%, MNaϩ) and 347 (100);
[Found (MNaϩ) 349.2708. C20H38NaO3 requires MNa,
349.2719].
m/z(EI) 222 (10%, Mϩ Ϫ H2O) and 69 (100); [Found (Mϩ
H2O) 222.1983. C15H26O requires M Ϫ H2O, 222.1984].
Ϫ
(6RS,12RS )-6,12-Dihydroxy-heptadecane 16a. Alcohol 16a
was prepared according to general procedure H from acetate 8a
(105 mg, 0.20 mmol) in THF (5 cm3), lithium naphthalenide
(2.0 cm3, 2.0 mmol, 1 mol dmϪ3 solution in THF) and MeOH
(5 cm3). Work-up as described above followed by flash column
chromatography (eluent – Et2O–petrol 1 : 1) and reduction
catalysed by Pd/C (100 mg, 10 wt.% Pd (dry basis) on activated
carbon) in EtOAc (5 cm3) afforded alkanol 16a (43 mg, 81%);
νmax(soln:CH2Cl2)/cmϪ1 3350 (OH); δH(400 MHz; CDCl3) 3.59
(2 H, m, 6-H and 12-H), 1.62–1.05 (28 H, m, 2-H × 2, 3-H × 2,
4-H × 2, 5-H × 2, 7-H × 2, 8-H × 2, 9-H × 2, 10-H × 2, 11-H ×
2, 13-H × 2, 14-H × 2, 15-H × 2, 16-H × 2 and OH × 2) and
0.90 (6 H, t, J 6.9, 1-H × 3 and 17-H × 3); δC(100 MHz; CDCl3)
72.0, 37.5, 37.4, 31.9, 29.7, 25.6, 25.3, 22.6 and 14.0; m/z(FAB)
273 (10%, MHϩ), 149 (100); [Found (MHϩ) 273.2787. C17H37O2
requires MH, 273.2794].
(2RS,4SR)-2,10-Di(tert-butyl-dimethyl-silanyloxy)-4-
hydroxy-decane 18. Method 1: alcohol 18 was prepared accord-
ing to general procedure I from diene mixture 13c, 14c and 15c
(0.26 : 0.67 : 0.07) (90 mg, 0.22 mmol) with Pd/C (90 mg,10
wt.% Pd (dry basis) on activated carbon) in EtOAc (2 cm3).
After 2 hours work-up as described above afforded alkanol
18 as an oil (91 mg, 100%); [α]2D5 Ϫ13.6 (c 0.25 in CH2Cl2);
νmax(film)/cmϪ1 3425 (OH); δH(600 MHz; CDCl3) 4.08 (1 H, m,
2-H), 3.74 (1 H, m, 4-H), 3.59 (2 H, t, J 6.6, 10-H × 2), 1.55–
1.28 (12 H, m, 3-H × 2, 5-H × 2, 6-H × 2, 7-H × 2, 8-H × 2, 9-H
× 2 and OH), 1.18 (3 H, d, J 6.2, 1-H × 3), 0.91 (9 H, m,
SiC(CH3)3 × 1), 0.89 (9 H, m, SiC(CH3)3 × 1), 0.12 (3 H, m,
Si(CH3) × 1), 0.11 (3 H, m, Si(CH3) × 1) and 0.04 (6 H, m,
Si(CH3) × 2); δC(150 MHz; CDCl3) 71.5, 70.2, 63.3, 45.8, 37.6,
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3206

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32.8, 29.5, 25.9, 25.8, 25.8, 25.4, 24.6, 18.3, 17.9, Ϫ3.9, Ϫ4.8,
Ϫ5.3 and Ϫ5.3; m/z (ES) 441 (100%, MNaϩ); [Found (MNaϩ)
441.3178. C22H50NaO3Si2 requires MNa, 441.3196].
the Novartis Research Fellowship (S. V. L.) for support of this
work, and E. A. Wright for helpful discussions.
Method 2: alcohol 18 was prepared according to general
procedure I from diene mixture 13c, 14c and 15c (0.62 : 0.15 :
0.23) (71 mg, 0.17 mmol) with Pd/C (71 mg, 10 wt.% Pd (dry
basis) on activated carbon) in EtOAc (2 cm3). After 2 hours
work-up as described afforded alkanol 18 as an oil (70 mg,
98%). Data were consistent with those reported (vide supra).
References
1 For recent reviews see: T. J. Donohoe, Contemp. Org. Synth., 1996, 1;
A. C. Comely, S. E. Gibson and S. Sur, J. Chem. Soc., Perkin Trans.
1, 2000, 109; T. J. Donohoe, R. R. Harji, P. R. Moore and M. J.
Waring, J. Chem. Soc., Perkin Trans. 1, 1998, 819; T. J. Donohoe,
P. M. Guyo, P. R. Moore and C. A. Stevenson, Contemp. Org.
Synth., 1997, 22.
(3RS,9RS )-3-(tert-Butyl-dimethyl-silanyloxy)-9-hydroxy-2-
methyl-tetradecane 19a. Alcohol 19a was prepared according
to general procedure I from diene mixture 13d, 14d and 15d
(0.62 : 0.20 : 0.18) (30 mg, 0.08 mmol) with Pd/C (30 mg, 10
wt.% Pd (dry basis) on activated carbon) in EtOAc (1 cm3).
After 2 hours work-up as described above afforded alkanol 19a
as an oil (30 mg, 99%); νmax(film)/cmϪ1 3421 (OH); δH(600 MHz;
CDCl3) 3.60 (1 H, m, 9-H), 3.41 (1 H, m, 3-H), 1.68 (1 H, m,
2-H), 1.56–1.28 (19 H, m, 4-H × 2, 5-H × 2, 6-H × 2, 7-H × 2,
8-H × 2, 10-H × 2, 11-H × 2, 12-H × 2, 13-H × 2 and OH),
0.89 (12 H, m, 14-H × 3 and SiC(CH3)3), 0.85 (3 H, d, J 6.8,
2-CCH3), 0.83 (3 H, d, J 6.8, 1-H × 3) and 0.02 (6 H, s, Si(CH3)
× 2); δC(150 MHz; CDCl3) 76.8, 72.0, 37.4, 33.1, 32.7, 31.9,
30.0, 25.9, 25.6, 25.5, 25.3, 22.6, 18.2, 18.1, 17.6, 14.1, 14.0,
Ϫ4.3 and Ϫ4.5; m/z (EI) 341 (40%, Mϩ Ϫ OH) and 69 (100);
[Found (Mϩ Ϫ OH) 341.3250. C21H45OSi requires M Ϫ OH,
341.3240].
2 S. V. Ley, L. R. Cox and G. Meek, Chem. Rev., 1996, 96, 423;
L. R. Cox and S. V. Ley, Chem. Soc. Rev., 1998, 27, 301.
3 R. Aumann, H. Ring, C. Krüger and R. Goddard, Chem. Ber., 1979,
3644.
4 (a) G. D. Annis and S. V. Ley, J. Chem. Soc., Chem. Commun., 1977,
581; (b) G. D. Annis, S. V. Ley, C. R. Self and R. Sivaramakrishnan,
J. Chem. Soc., Perkin Trans. 1, 1981, 270.
5 (a) S. V. Ley, S. Burckhardt, L. R. Cox and J. M. Worrall,
Chem.Commun., 1998, 229; (b) S. V. Ley, S. Burckhard, L. R.
Cox and J. M. Worrall, J. Chem. Soc., Perkin Trans. 1, 2000,
211.
6 (a) W. R. Bates, E. Fernández-Megía, S. V. Ley, K. Rück-Brown
and D. M. G. Tilbrook, J. Chem. Soc., Perkin Trans. 1, 1999, 1917;
(b) D. Diéz-Martin, N. R. Kotecha, S. V. Ley, S. Mantegani,
J. C. Menendez, H. M. Organ, A. D. White and B. J. Banks,
Tetrahedron, 1992, 7899; (c) S. V. Ley and G. Meek, J. Chem. Soc.,
Perkin Trans. 1, 1997, 1125; (d ) A. M. Horton and S. V. Ley,
J. Organomet. Chem., 1985, 285, C17; (e) A. Armstrong,
D. Diez-Martin, M. J. Ford, P. Grice, J. G. Knight, H. C. Holt,
S. V. Ley, A. Madin, S. Mukherjee, A. M. Z. Slawin, S. Vile, A. D.
White, D. J. Williams and M. Woods, J. Chem. Soc., Perkin Trans. 1,
1991, 667; ( f ) R. W. Bates, R. Fernandez-Moro and S. V.
Ley, Tetrahedron, 1991, 9929; (g) J. G. Knight and S. V. Ley,
Tetrahedron Lett., 1991, 9929; (h) S. Burckhardt and S. V. Ley,
J. Chem. Soc., Perkin Trans. 1, 2000, 3028; (i) C. J. Hollowood, S. V.
Ley and S. Yamanoi, Chem. Commun., 2002, 1624; (j) S. Burckhardt
and S. V. Ley, J. Chem. Soc., Perkin Trans. 1, 2002, 874; (k) C. J.
Hollowood, S. Yamanoi and S. V. Ley, Org. Biomed. Chem., 2003, 1,
1684.
7 (a) S. V. Ley and E. A. Wright, J. Chem. Soc., Perkin Trans. 1, 2000,
1677; (b) S. V. Ley, L. R. Cox, B. Middleton and J. M. Worrall,
Chem. Commun., 1998, 1339; (c) S. V. Ley and L. R. Cox, Chem.
Commun., 1998, 227.
8 S. V. Ley, L. R. Cox, G. Meek, K. H. Metten, C. Pique and
J. M. Worrall, J. Chem. Soc., Perkin Trans. 1, 1997, 3299.
9 (a) S. V. Ley and L. R. Cox, J. Chem. Soc., Perkin Trans. 1,
1997, 3315; (b) S. V. Ley, S. Burckhardt, L. R. Cox and G. Meek,
J. Chem. Soc., Perkin Trans. 1, 1997, 3327; (c) S. V. Ley, S.
Burckhardt, L. R. Cox and J. M. Worrall, Chem. Commun., 1998,
229.
(6RS,12RS )-6-(tert-Butyl-dimethyl-silanyloxy)-12-hydroxy-
heptadecane 19b. Alcohol 19b was prepared according to gener-
al procedure G from acetate 11b (70 mg, 0.12 mmol) in THF
(3 cm3) and lithium naphthalenide (0.58 cm3, 0.58 mmol, 1 mol
dmϪ3 solution in THF). Work-up as described above followed
by flash column chromatography (eluent – Et2O–petrol 1 : 3
1
: 1) and reduction catalysed by Pd/C (70 mg, 10 wt.% Pd (dry
basis) on activated carbon) in EtOAc (3 cm3) afforded alkanol
19b (40 mg, 89%); νmax(soln:CH2Cl2)/cmϪ1 3423 (OH); δH(400
MHz; CDCl3) 3.60 (2 H, m, 6-H and 12-H), 1.58–1.15 (27 H, m,
2-H × 2, 3-H × 2, 4-H × 2, 5-H × 2, 7-H × 2, 8-H × 2, 9-H × 2,
10-H × 2, 11-H × 2, 13-H × 2, 14-H × 2, 15-H × 2, 16-H × 2 and
OH), 0.90 (15 H, m, 1-H × 3, 17-H × 3 and SiC(CH3)3) and 0.04
(6 H, s, Si(CH3) × 2); δC(100 MHz; CDCl3) 72.4, 72.0, 37.8,
37.8, 37.5, 37.4, 32.1, 31.9, 29.6, 25.9, 25.9, 25.6, 25.3, 25.0,
22.6, 22.6, 18.1, 14.0, 14.0, Ϫ4.4 and Ϫ4.4; m/z (FAB) 386 (20%,
Mϩ), 215 (100); [Found (Mϩ) 386.3584. C23H50O2Si requires M,
386.3580].
10 (a) S. V. Ley, L. R. Cox and J. M. Worrall, J. Chem.
Soc., Perkin Trans. 1, 1998, 3349; (b) S. V. Ley, L. R. Cox, B.
Middleton and J. M. Worrall, Tetrahedron, 1999, 3515.
11 C. J. Hollowood and S. V. Ley, Chem. Commun., 2002,
2130.
12 R. D. Pike, Encyclopedia of reagents for organic synthesis,
ed. L. A. Paquette, Wiley, New York, 1995.
Acknowledgements
We thank the EPSRC (C. J. H.), the Isaac Newton Trust
Bursary Scheme (C. J. H.), the B. P. Endowment (S. V. L.) and
O r g . B i o m o l . C h e m . , 2 0 0 3 , 1, 3 1 9 7 – 3 2 0 7
3207