Transformations of 4,5-substituted (4S,5S)-2,2-dimethyl-1,3-dioxolanes

Article abstract of DOI:10.1023/A:1013986304683

(4S,5S)-4,5-Bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane treated with trifluoromethanesulfonyl chloride in pyridine undergoes tandem substitution of one hydroxy group by a triflate group, and the other by pyridinium moiety. In neutral solvents the (4S,5S)-4,5-bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane dilithium salt reacts with trifluoromethanesulfonyl chloride affording both triflates and chlorides and also suffers a cleavage of the dioxolane ring followed by transformations of acyclic products. A triflate cationic complex rhodium cyclooctadiene (4S,5S)-2,3-dihydroxy-1,4-bis(dimemylamino)-2,3-O-isopropylidenebutane was prepared and used as catalyst for hydrogenation of α-acetamidocinnamic and itaconic acids.

Full text of DOI:10.1023/A:1013986304683

Russian Journal of Organic Chemistry, Vol. 37, No. 12, 2001, pp. 1757 1761. Translated from Zhurnal Organicheskoi Khimii, Vol. 37, No. 12, 2001,
pp. 1838 1842.
Original Russian Text Copyright
2001 by Shainyan, Ustinov, Nindakova.
Dedicated to Academician M. G. Voronkov on occasion of his 80th birthday
Transformations of 4,5-Substituted
4S,5S)-2,2-Dimethyl-1,3-dioxolanes
(
B. A. Shainyan, M. V. Ustinov, and L. O. Nindakova
Faworsky Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, Irkutsk, 664033, Russia
Received June 26, 2000
Abstract (4S,5S)-4,5-Bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane treated with trifluoromethanesulfonyl
chloride in pyridine undergoes tandem substitution of one hydroxy group by a triflate group, and the other
by pyridinium moiety. In neutral solvents the (4S,5S)-4,5-bis(hydroxymethyl)-2,2-dimethyl-1,3-dioxolane
dilithium salt reacts with trifluoromethanesulfonyl chloride affording both triflates and chlorides and also
suffers a cleavage of the dioxolane ring followed by transformations of acyclic products. A triflate cationic
complex rhodium cyclooctadiene (4S,5S)-2,3-dihydroxy-1,4-bis(dimethylamino)-2,3-O-isopropylidenebutane
was prepared and used as catalyst for hydrogenation of -acetamidocinnamic and itaconic acids.
2
,3-Dihydroxy-1,4-bis(diphenylphosphino)-2,3-O-
Scheme 1.
isopropylidenebutane (DIOP) (Ia) is widely used as
chelating ligand in catalysts for chiral hydrogenation.
It is prepared by replacing the p-tolyenesulfonic
group in tosylate Ib by Ph P moiety [1].
2
Ia f
I, X = PPh (a), OTs (b), NMe (c), OTf (d), OH (e),
2
2
Cl (f).
(
hydroxymethyl)-2,2-dimethyl-1,3-dioxolane
(Ie)
with trifluoromethanesulfonyl chloride in pyridine
alongside the target compound Id formed as the main
product a salt, (4S,5S)-1-(2,2-dimethyl-5-trifluoro-
methylsulfonyloxymethyl-1,3-dioxolan-4-yl)pyridin-
ium chloride (II) (Scheme 1).
The nitrogen analogs of DIOP, optically active
diamines of type I (X = NH , NR ) are known as
2
2
chiral catalysts for polymerization into highly regular
polymers [2] and also as ligands for preparation of
platinum(II) salts complexes possessing antitumor
properties [3, 4]. Aiming at preparation and study of
properties of chiral catalysts based on nitrogen
analogs of DIOP we synthesized a rhodium complex
of (4S,5S)-2,3-dihydroxy-1,4-bis(dimethylamino)-2,3-
The assignment of signals in H and 13C NMR
1
spectra was carried out with the use of two-dimen-
O-isopropylidenebutane
(Ic)
(DIODMA)
and
investigated hydrogenation of prochiral aminoacids
catalyzed therewith. We also attempted to introduce
into the molecule more nucleofugal group through a
synthesis of the corresponding bistriflate Id in order
to facilitate functionalization of compounds from I
series.
The attempt to prepare bistriflate Id gave an un-
expected result: in the reaction of (4S,5S)-4,5-bis-
1
070-4280/01/3712-1757$25.00 2001 MAIK Nauka/Interperiodica

1
758
SHAINYAN et al.
sional spectrum H 13C HETCOR. Since trifluoro-
methanesulfonyl chloride can operate both as
sulfonating and chlorinating agent [5] the following
scheme is presumable to rationalize formation of salt
II: One hydroxy group is sulfonated, the other
chlorinated, and then the intermediate chloride III is
alkylated by pyridine.
1
(CH H ). Also appears a broadened signal at 3.6
A
B
1
3
19
3.7 ppm (in deuteroacetone). The C and F spectra
confirm the presence of triflate group. All this
evidence suggests formation of 2,3-dihydroxybutane-
1,4-bis(trifluoromethanesulfonate) (V) as a result of
dioxolane ring opening effected by acid traces (HCl
in CF SO Cl) (Scheme 2).
3
2
Reaction product II arose also on performing
reaction in THF when pyridine was used in equimolar
amount just for scavenging liberating HCl. The
chlorinating action of trifluorosulfonyl chloride was
directly confirmed by isolation of (4S,5S)-2,2-di-
methyl-4,5-bis(chloromethyl)-1,3-dioxolane (If) in
reaction of diol Ie with an equimolar amount of
pyridine in dioxane.
Scheme 2.
In reaction of diol Ie with trifluoromethanesulfonyl
chloride in the absence of bases was obtained 1,2,3,4-
butanetetrol (threitol) (IV) resulting from dioxolane
ring cleavage with acetone elimination. The process
is apparently catalyzed by HCl traces present in the
acyl chloride or liberating at its reaction with diol Ie.
1
In The H NMR spectrum of compound V in
CD OD the signals of the fragment CH CH are
3
2
shifted upfield by 0.4 ppm compared to its spectrum
in acetone-d ; in the course of time their intensity
6
decreases, and appears and grows in intensity a new
group of peaks. The transformation product VI
isolated when the signals of compound V disappeared
was a crystalline substance of low melting point with
no signals in the 19F NMR spectrum. The signals of
diastereotopic protons from CH2 group suffer a
strong upfield shift o a region characteristic of CH2
groups (3.37 and 3.44 ppm), and the signal from
CH proton appears downfield from those of CH2
The target bistriflate Id was obtained by reacting a
dilithium salt of diol Ie with CF SO Cl in hexane.
3
2
(
3.68 ppm) unlike the spectra of compounds Id, V.
This spectral pattern is consistent with 1,4-dimeth-
1
oxybytane-2,3-diol (VI) structure. The H NMR
spectrum published for this structure registered in
D O [7] (mp 28 C [6]) has signals a little displaced
2
Note a considerable dependence of the chemical
shifts of bis-triflate Id signals in the H NMR
spectrum on the solvent: all the signals suffer in
benzene a strong upfield shift as compared to
(by 0.1 ppm) due to the solvent effect; however the
relative chemical shifts and the coupling constants are
in agreement with our data thus confirming the
assumed structure. The formation of 2,3-dimethoxy-
butane-1,4-diol, isomer of compound VI, is excluded
1
spectrum registered in chloroform:
(CH ) 0.85,
A
1
(
CH ) 1.01, (CH) 0.89, (CH ) 0.36 ppm.
since in the H NMR spectrum of this compound the
B
3
1
3
The corresponding shifts in the C NMR spectrum
do not exceed 0.5 ppm.
resonance of methine protons appears upfield
(3.54 ppm) from the methylene signal (3.78 ppm) [8];
we have not observed such signals in the spectrum of
the reaction mixture under study.
On storage of compound Id solution in chloroform
for 3 4 days forms a new compound lacking in the
1
H NMR spectrum the signal from C(CH ) group;
Compound V can be obtained directly from lithium
salt of diol Ie by treating it with CF SO Cl in
3
2
however are conserved the signals from the CHCH2
fragment with diastereotopic protons of the methylene
group: 4.46 ppm (CH) and 4.90 and 5.01 ppm
3
2
dioxane. It should be noted that apart compounds
IV VI were formed also other transformation pro-
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 12 2001

TRANSFORMATIONS OF 4,5-SUBSTITUTED (4S,5S)-2,2-DIMETHYL-1,3-DIOXOLANES
H NMR spectra of diamine Ic and its rhodium complex ( , ppm, J, Hz)
1759
1
Solvent
(CH), m
(CH ) (H ), d.d
(CH ) (H )
(CH N), s
(CH C), s
2
A
2
B
3
3
Benzene-d6
Chloroform-d
Acetone-d6
3.91
3.77
3.80
4.10
2.47, JAB 12.99, JAC 3.47
2.49, JAB 12.8, JAC 6.77
2.52, JAB 12.99, JAC 3.65
3.02, JAB 12.80, JAC 7.10
2.37 d.d, JBC 5.86
2.38 d
2.37 d.d, JBC 6.20
2.96 d.d, JBC 4.60
2.13
2.28
2.21
2.68
1.35
1.39
1.29
1.36
a
Acetone-d6
a
Rhodium complex.
1
A conformation should be 3J
3J whereas
ducts containing in the H NMR spectra signals from
CH CH2 fragment with diastereotopic methylene
protons. Their isolation and identification will be the
subject of future studies.
<
HA
HB
3
3
in B conformation J
>
JHB. It is reasonable to
HA
assume that in both conformations the downfield
signal corresponds to the same proton HA, then the
observed spectral changes are consistent with the
change in conformation from A to B that are shown
below in Newman projections:
The nitrogen analog of DIOP, DIODMA (Ic) was
obtained by cyclization of (+)-tartaric acid diamide
VII) under the action of 2,2-dimethoxypropane
(
followed by reduction of dicarboxamide VIII with
lithium aluminum hydride along procedure [6].
Diamine Ic afforded a chelate cationic complex
1
with rhodium that is supported by H NMR spectrum
where to the strongest downfield shift are subjected
the protons of NMe groups (0.47 ppm) and the
diastereotopic methylene protons (0.50 and
0
.59 ppm). On going from the complex center the
Thus the rhodium complex containing one or two
downfield shift decreases (0.3 ppm for CH protons
and 0.07 ppm for CMe groups). The spectra of the
free ligand and the complex were registered in the
same solvent, acetone-d . In the C NMR spectrum
on the contrary the signals are shifted upfield:
molecules of diamine Ic may be assigned the com-
+
position
{Rh[( )S,S-DIODMA]n solv } CF SO
m
3
3
(IX), where n = 1 or 2. Complex IX was tested in
hydrogenation of prochiral substrates, itaconic and
-acetamidocinnamic acids. The hydrogenation was
carried out with molecular hydrogen under mild
conditions (p 1 at, 40 C); the conversion of itaconic
and -acetamidocinnamic acids into R(+)- -methyl-
succinic acid and S(+)-N-acetylphenylalanine was
1
3
6
(
(
CH) 1.73,
(CH2) 2.17,
(NMe) 1.06,
CMe) 0.43 ppm. In the spectrum of the complex
with diamine Ic are lacking the signals from cyclo-
octadiene that have appeared in the initial complex
obtained by reaction of [(COD)RhCl] with silver
7
0 and 15% respectively. The asymmetrization
2
attained with complex IX was lower than at the use
of the diphosphine analogs [9]: optical yields of the
products of enantioselective hydrogenation of itaconic
and -acetamidocinnamic acids were 17.4 and 30%
respectively. The moderate optical yield of the pro-
ducts may be ascribed to gradual decomposition of
diamine complex IX under reductive conditions with
liberation of metallic rhodium as is observed in the
course of experiment.
triflate. This means that ligand exchange occurred,
and the diene molecule was displaced by diamine Ic.
The data in the table evidence that the prevailing
conformation of diamine Ic changes on complexing.
In the spectrum of free ligand Ic the downfield signal
of the diastereotopic pair of protons CH H is split on
A
B
H with a smaller coupling constant, the spectrum
C
pattern in the complex is the opposite. We believe
that this fact indicates a change in the conformation:
that of the free ligand is apparently conformation A
where the gauche-interactions of the bulky groups is
minimal; at complexing both nitrogen atoms should
be directed to the central rhodium atom, and this is
possible only in B conformation. Taking into account
the angular dependence of the coupling constants, in
EXPERIMENTAL
IR spectra were recorded on IKS-29 device from
1
13
19
thin films. H, C, and
NMR spectra were
registered on spectrometer Bruker DPX 400 at 400,
100, and 376 MHz respectively from solutions in
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 12 2001

1
760
SHAINYAN et al.
CDCl using HMDS as internal reference. Chemical
at reduces pressure. The oily substance obtained was
separated from the precipitating crystals of pyridin-
ium hydrochloride, was treated with water, three
times with chloroform, the extract was filtered, the
solvent was distilled off, and product If was purified
3
shifts are given relative to TMS. GC-MS analyses
were carried out on LKB 2091 instrument. GLC was
performed on a chromatograph LKhM-80 equipped
with columns 1000 3 mm, stationary phase 5%
SE-30 on Chromaton N-AW-DMCS, detector
katharometer, carrier gas helium. Optical rotation
was measured on Polamat A instrument at 546 nm
wavelength and was recalculated to 589 nm wave-
length with a factor 1.17543.
1
by microdistillation. Yield 0.2 g (10%). H NMR
spectrum, , ppm: 1.43 s (6H, Me C), 3.68 m (4H,
2
1
3
CH Cl), 4.15 m (2H, CH).
C NMR spectrum,
2
1
13
C, ppm: 27.20 q.q [CH , J(H C) 126.7,
J(H C) 3.0 Hz], 44.42 t.m [4H, CH Cl, J(H C)
3
3
13
1
13
2
4
4
5
5
1
13
(
4S, 5S)-4, 5-Bis(aminomethyl)-N ,N ,N ,N ,-
,2-hexamethyl-1,3-dioxolane (Ic) was obtained
along procedure [6]. bp 41 C/1 mm Hg (publ.
151.3 Hz], 78.58 d.m [CH, J(H C) 150.9 Hz],
2
110.57 m (CMe2).
(
4S, 5S)-1-(2, 2-Dimethyl-5-trifluoromethyl-
1
5
4 C/0.8 mm Hg [6]). H NMR spectrum, , ppm:
sulfonylmethyl-1,3-dioxolan-4-ylmethyl)pyridin-
ium chloride (II). To a solution of 3.17 g (0.02 mol)
of compound Ie in 20 ml of dry pyridine was added
dropwise at 15 C 5.7 ml (0.06 mol) of CF SO Cl.
1
.39 s (6H, Me C), 2.28 s (12H, NMe ), 2.38 d (2H,
2
2
2
H in CH ), 2.50 d.d [2H, H in CH , J(H H )
1
A
2
B
2
A
B
3
2.6, J(HH) 6.8 Hz], 3.77 m (2H, CH) {publ. (in
3
2
*
CCl ): 1.32 s, 3.34 m, 3.50 m, 3.85 m [6]}.
4
The reaction mixture was stirred for 20 h at 25
5 C and was then evaporated till dryness on a
1
3
C NMR spectrum, acetone-d6, C, ppm: 27.66
1
(
CCH ), 46.74 (NCH ), 62.77 (CH ), 79.63 (CH),
3
3
2
rotary evaporator. To remove pyridine completely
the residue was treated with chloroform, acidified
with HCl till pH 3, heated to boiling, then cooled
to 0 C, the separated colorless crystals of pyridine
hydrochloride were filtered off, the filtrate was
evaporated till dryness, the residue was dissolved in
20 ml of water, and compound II was extracted into
dichloromethane. To isolate salt II the organic extract
was washed with water, and the water layer was
1
09.11 (CCH3).
(
4S,5S)-2,2-Dimethyl-4,5-bis(trifluoromethyl-
sulfonyloxymethyl)-1,3-dioxolane (Id). To a disper-
sion of 0.53 g (3.05 mmol) of diol Ie bis-lithium salt
in 8 ml of hexane was added dropwise at 5 10 C
while stirring 0.65 ml (6 mmol) of CF SO Cl in
3
2
2
ml of hexane. The mixture was vigorously stirred
for 2 3 h and then the precipitate of lithium salts
LiCl and CF SO Li) was filtered off. The hexane
(
evaporated till dryness. Yield 1 g (15%), mp 99
3
2
1
and excess acyl chloride was removed under reduced
pressure without heating. The separated needle-like
crystals were filtered off, washed with cold ( 10 C)
hexane, and dried in a vacuum. Yield 0.42 g (32%).
100 C. [ ]546 37.8 (c 10.8, CHCl ). H NMR
3
spectrum, , ppm: 1.36 and 1.41 s (6H, Me C),
2
2
3
3.81 m [2H, H + H , J(H H ) 12.0, J(H H )
C
D
C
D
C
Y
3
2
5.0, J(H H 5.4 Hz], 4.11 m [1H, H , J(H H )
D
Y
Y
X
Y
1
3
3
mp 30 C. [ ]546 8.1 (c 2.2, hexane). H NMR
8 Hz], 4.31 m [1H, H , J(H H ) 8.8, J(H H )
X
A
X
B
X
spectrum in CDCl3, , ppm: 1.44 s (6H, Me C),
2
2
2.2 Hz], 4.80 d.d [1H, H , J(H H ) 13.7 Hz], 5.11
d.d (1H, H ), 8.07 t (2H, H , J 7.0 Hz), 8.55 t (1H,
H ), 8.98 d (2H, H , J 6.1 Hz). C NMR spectrum,
A A B
4
.22 m (2H, CH), 4.56 d (2H, H in CH ), 4.65 d
3
A
2
2
13
B
m
[
2H, HB in CH2, J(H H ) 11.0 Hz]. C NMR
3
13
A
B
p
o
spectrum, , ppm: 26.88 (CH ), 73.52 (CH ), 74.52
C
3
2
C, ppm: 26.93 and 27.06 (CH ), 43.68 (CH N),
3
2
(
3
CH), 112.21 (OCO), 118.82 q [CF , J(C F)
3
19.4 Hz]. 1 F NMR spectrum (CCl F), F, ppm:
9
63.42 (CH O), 77.39 (CCO), 77.83 (CCN),
2
3
1
1
11.73 (OCO), 120.70 q [CF , J(C F) 319.6 Hz],
3
7
5.14. Found, %: C 25.24; H 2.87; F 27.22; S
1
9
28.26 (C ), 145.63 (C ), 146.20 (C ). F NMR
1
2
5.77. C H F O S . Calculated, %: C 25.36; H
.84; F 26.74; S 15.04.
m
o
p
9
12
6
8 2
spectrum (CCl F), F, ppm: 79.25 ppm Found, %:
3
C 39.74; H 4.31; Cl 9.66; F 15.00; N 3.62; S 8.27.
C H ClF NO S. Calculated, %: C 39.85; H 4.37;
(
4S,5S)-2,2-Dimethyl-4,5-bis(chloromethyl)-1.3-
1
3
17
3
5
dioxolane (If). To a solution of 1.73 g (10.7 mmol)
of diol Ie and 5 ml of pyridine in dioxane at 0 C was
added dropwise with stirring within 1 h 1.5-fold
Cl 9.05; F 14.55; N 3.58; S 8.18. 1,2,3,4-Butane-
1
tetrol (IV). mp 89 C [10]. H NMR spectrum,
DMSO-d , , ppm: 3.33 m (2H, CH), 3.43 m (4H,
6
excess of CF SO Cl. The mixture was left overnight,
3
2
CH ), 4.20 br.s (4H, OH).
2
then solvents and excess acyl chloride were removed
(
2S,3S)-2,3-Dihydroxybutane-1,4-bis(trifluoro-
*
The figure is obviously wrong; apparently, the value is
methanesulfonate) (V). To a dispersion of 0.53 g
(3.3 mmol) of diol Ie bis-lithium salt in 8 ml of
2
2.34 ppm.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 12 2001

TRANSFORMATIONS OF 4,5-SUBSTITUTED (4S,5S)-2,2-DIMETHYL-1,3-DIOXOLANES
1761
dioxane was added dropwise at 5 10 C while stirring
.05 ml (10.9 mmol) of CF SO Cl in 2 ml of di-
The chemical yield of hydrogenated products was
evaluated from the H NMR spectra of the reaction
1
1
3
2
oxane. The mixture was vigorously stirred for 2 3 h
and then the precipitate of lithium salts was filtered
off, and the filtrate was left standing for 24 h; the
solution turned red. Dioxane was removed in a
vacuum, to the residue was added 5 7 ml of hot
chloroform and after stirring the mixture was cooled,
and the separated crystals were filtered off. After the
second treating with chloroform we obtained 0.64 g
mixtures by the ratio of the integral intensity of
acetyl groups of the initial substrate at 2.08 ppm and
of the hydrogenated product at 1.88 ppm (for
-acetamidocinnamic acid). With itaconic acid was
used the ratio of intensities for the signals from the
=
CH group of the initial substrate (6.27 ppm) and
2
CH group (1,19 d ppm) in the hydrogenated product.
3
(
50%) of compound V as colorless crystals. mp
REFERENCES
9
1
3
7 99 C. [ ]5
: 1). H NMR spectrum, acetone-d6, , ppm:
14.8 (c 1.36, hexane acetone,
46
1
1
. Murrer, B.A., Brown, J.M., Chaloner, P.A., Nichol-
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Sci., Polym. Lett. Ed., 1983, vol. 21, no. 8,
pp. 601 607.
.64 br.s (2H, OH), 4.46 m (2H, CH), 4.90 m (2H,
2
CH ), 5.01 m [2H, CH n, J(H H n) 11.1 Hz].
A
i
A
i
1
3
C NMR spectrum, acetone-d6,
, ppm: 74.00
C
1
(
3
CH2), 75.34 (CH), 118.60 q [CF3, J(CF)
18.5 Hz]. 1 F NMR spectrum, acetone-d6, F, ppm:
9
7
1.67. Found, %: C 18.54; H 2.65; F 29.06; S
3
. US Patent, 5395947, 1993; Chem. Abstr., 1993,
vol. 118, P224389b.
1
2
6.54. C H F O S . Calculated, %: C 18.66; H
6
8
6
8 2
.09; F 29.51; S 16.60.
4
. Kim, D.K., Kim, G., Gam, J., Cho, Y.B., Kim, H.T.,
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4
4
5
5
(
4R,5R)-N ,N ,N ,N ,2,2-Hexamethyl-1,3-di-
oxolane-4,5-dicarboxamide VIII was obtained by
procedure [6]. mp 82 C [6]. H NMR spectrum, ,
ppm: 1.44 s (6H, Me C), 2.95 and 2.16 s (6H,
NMe ), 5.22 s (2H, CH) [publ. (in CCl ): 1.38 s,
1
5
2
2
4
2
.92 s, 3.16 s, 5.09 3s [6]).
Hydrogenation of itaconic and -acetylamino-
cinnamic acids. Hydrogenation was carried out at
constant temperature with vigorous shaking of a glass
reactor connected to a manometer and a system of
hydrogen input. The gas was purified and dried by
standard procedure. Into the reactor in the hydrogen
flow was charged 5 ml of methanol and about 1 mmol
of substrate. Then the pressure was raised to 1.2
7
. Potvin, P.G., Gau, R., Kwong, P.C.C., and Bian-
chet, S., Canad. J. Chem., 1989, no. 10,
pp. 1523 1537.
8
9
. Cope, A.C. and Mehta, A.S., J. Am. Chem. Soc.,
1
964, vol. 86, no. 24, pp. 5626 5630.
. Nindakova, L.O., Shainyan, B.A., Albanov, A.I.,
and Ustinov, M.V., Zh. Org. Khim., 2000, vol. 36,
no. 11, pp. 1660 1665.
1
.3 at, and with hypodermic syringe was added either
solution of an individual complex or of catalyst
prepared in situ in a separate flask under argon
atmosphere in 5 ml of a mixture methanol benzene
10. Svoistva org. soed. (Properties of Organic Com-
pounds), Potekhin, A.A., Ed., Leningrad: Khimiya,
1984, p. 350.
(
2: 1). At this moment the shaking was switched on.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 37 No. 12 2001