Synthesis of platinum complexes containing (+)-bornyl- and (-)-menthylammonium in the outer coordination sphere and their catalytic activity in hydrosilylation reactions

Article abstract of DOI:10.1007/s11172-008-0054-3

Optically active (+)-bornyl- and (-)-menthylammonium platinates were synthesized starting from H₂[PtCl₆] ? 4H₂O and hydrochlorides of the corresponding amines. Catalytic activity of the complexes in the hydrosilylation reactions of 1,3-divinyl-1,1,3,3- tetramethyldisiloxane with 1,1,3,3-tetramethyldisiloxane and acetophenone with diphenylsilane was studied. The addition of the siloxanes leads to a predominant formation of β-adduct. Activity of the catalysts, evaluated on the 50% conversion of the substrate, decreases in the following sequence: (-)-(menthylNH₃)₂[PtCl₆] > (Et ₃NH)₂[PtCl₆] > (+)-(bornylNH ₃)₂[PtCl₄] > (+)-(bornylNH₃) ₂[PtCl₆]. Asymmetric induction is observed in the hydrosilylation of aceto-phenone in the presence of (+)-(bornylNH ₃)₂[PtCl _n ] (n = 4, 6); (+)-(bornylNH ₃)₂[PtCl₆] showed the highest catalytic activity and selectivity. The hydrosilylation of acetophenone gave 1-phenylethoxy(diphenyl)silane, 1-phenylvinyloxy(diphenyl)silane, and 2-phenylethyl-2-diphenylsiloxy(diphenyl)silane as the products.

Full text of DOI:10.1007/s11172-008-0054-3

Russian Chemical Bulletin, International Edition, Vol. 57, No. 2, pp. 349—357, February, 2008
349
Synthesis of platinum complexes containing (+)ꢀbornylꢀ and
(
–)ꢀmenthylammonium in the outer coordination sphere
and their catalytic activity in hydrosilylation reactions
ꢀ
D. A. de Vekki, V. M. Uvarov, A. N. Reznikov, and N. K. Skvortsov
St. Petersburg State Institute of Technology (Technical University),
2
6 Moskovskii prosp., 190013 St. Petersburg, Russian Federation.
Fax: +7 (812) 316 3144. Eꢀmail: hydrosilylation@newmail.ru
Optically active (+)ꢀbornylꢀ and (–)ꢀmenthylammonium platinates were synthesized startꢀ
ing from H [PtCl ]•4H O and hydrochlorides of the corresponding amines. Catalytic activity
2
6
2
of the complexes in the hydrosilylation reactions of 1,3ꢀdivinylꢀ1,1,3,3ꢀtetramethyldisiloxane
with 1,1,3,3ꢀtetramethyldisiloxane and acetophenone with diphenylsilane was studied. The
addition of the siloxanes leads to a predominant formation of βꢀadduct. Activity of the
catalysts, evaluated on the 50% conversion of the substrate, decreases in the following
sequence: (–)ꢀ(menthylNH ) [PtCl ] > (Et NH) [PtCl ] > (+)ꢀ(bornylNH ) [PtCl ] >
3
2
6
3
2
6
3 2
4
(
+)ꢀ(bornylNH ) [PtCl ]. Asymmetric induction is observed in the hydrosilylation of acetoꢀ
3 2 6
phenone in the presence of (+)ꢀ(bornylNH ) [PtCl ] (n = 4, 6); (+)ꢀ(bornylNH ) [PtCl ]
3
2
n
3 2
6
showed the highest catalytic activity and selectivity. The hydrosilylation of acetophenone gave
1
2
ꢀphenylethoxy(diphenyl)silane, 1ꢀphenylvinyloxy(diphenyl)silane, and 2ꢀphenylethylꢀ
ꢀdiphenylsiloxy(diphenyl)silane as the products.
Key words: terpenoids, аsymmetric induction, hydrosilylation, acetophenone, siloxanes,
platinates, (+)ꢀbornylamine, (–)ꢀmenthylamine.
Optically active coordination compounds with nitroꢀ
genꢀcontaining ligands are widely used for the achieveꢀ
ment of аsymmetric induction in the catalyzed transforꢀ
mations of prochiral unsaturated compounds. In such
catalysts, chiral centers are in the inner coordination
sphere of the metal complex.1—3 Ionic coordinating comꢀ
pounds, forming intimate contact pair with the metal,
belong to another promising type of optically active cataꢀ
lysts.4
was 50—55%) (Scheme 1). The yield of the target product
can be raised up to 67—74% by the use of propanꢀ2ꢀol
solution of hydrogen hexachloroplatinate with subsequent
precipitation of the product with diethyl ether.
Scheme 1
—11
H [PtCl ]•4H O + 2 RNH •НCl
(RNH ) [PtCl ]
3 2 6
2
6
2
2
It is known12—14 that ammonium platinum complexes
of the ionic type proved to be promising catalysts of
hydrosilylation reaction. In this connection, it seemed
reasonable to synthesize optically active ammonium
platinates, containing a chiral center in the outer coordiꢀ
nation sphere, to study their catalytic activity, and to
estimate their ability for the аsymmetric induction.
RNH =
,
2
The complexes are virtually insoluble in acetone, benꢀ
zene, dichloromethane, nitrobenzene, and ethanol; they
are soluble in DMSO and DMF, however, a dissolution
in DMSO can be accompanied by the partial changes in
the coordination sphere (for example, it is known that
the heating of [PtPy ]Cl or [PtPy Cl ] in DMSO easily
Results and Discussion
1
5
Synthesis of complexes. The reaction of aqueous
4
2
2
2
hydrogen hexachloroplatinate with excess (+)ꢀbornylꢀ or
leads to cisꢀ and transꢀ[Pt(DMSO)PyCl ]). In our case,
2
(
–)ꢀmenthylammonium hydrochlorides at room temperaꢀ
no incorporation of DMSO into the inner coordination
sphere is observed upon keeping of the complexes at 20 °C
for 3 h, however, a triplet signal of the coordinated DMSO
ture leads to the corresponding hexachloroplatinate(IV),
gradually precipitating from the reaction mixture (the yield
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 341—349, February, 2008.
066ꢀ5285/08/5702ꢀ0349 © 2008 Springer Science+Business Media, Inc.
1

350
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
de Vekki et al.
1
at δ 3.4—3.6 appears in the H NMR spectrum when the
temperature is raised to 60 °C.
Si—Vin), giving products of αꢀ, βꢀ, and diaddition, which
further are rapidly converted into the higher molecular
weight adducts. Such a behavior is in a good agreement
The IR spectra of (+)ꢀ(bornylNH ) [PtCl ] and
–)ꢀ(menthylNH ) [PtCl ] complexes contain characterꢀ
istic absorption bands in the far IRꢀregion: ν(Pt—Cl) at
3
2
6
1
7,18
(
with the literature data
threeꢀmolar excess (HMe Si) O. In the H NMR specꢀ
on the hydrosilylation with
3
2
6
1
2
2
–
1
3
30 and 333 cm .
trum of the reaction mixture, characteristic signals for the
The synthesis of bornylꢀ and menthylammonium
SiCH CH Si ethylene bridge (δ 0.42) and a doublet of the
2
2
tetrachloroplatinates(II) was accomplished by the action
of aqueous hydrazine on the corresponding hexachloroꢀ
Me group of the SiCHMeSi fragment (δ 1.01, J = 7.5 Hz)
are presented. The chromatoꢀmass spectrometric data of
the reaction mixtures confirm formation of the products
of αꢀ, βꢀ, and the succeeding additions of the siloxanes.
However, the retention times of the products differ
from those given in the literature (for example, for
1
6
platinates(IV) according to the standard procedure. The
reduction of (+)ꢀ(bornylNH ) [PtCl ] proceeds slowly
3
2
6
and affords expected (+)ꢀ(bornylNH ) [PtCl ] (ν(Pt—Cl)
3
2
4
–
1
3
16 cm ), whereas (–)ꢀ(menthylNH ) [PtCl ] complex
3 2 6
is immediately reduced to platinum metal, which, probꢀ
ably, results from the high lability of (–)ꢀ(menthylꢀ
NH ) [PtCl ] formed.
αꢀ and βꢀadducts, t = 3.4 and 3.3 min, whereas in
r
Ref. 18, t = 24 and 22 min, respectively), as well as
r
intensities of the base peaks, which can be explained
by different conditions for the spectra recording. In
the mass spectra of the GC peaks, the molecular ion
signals are absent; the base peak depends on the strucꢀ
ture and molecular weight of the compound (for the
products, containing terminal Si—H and Si—Vin
groups, the base peak, as a rule, is the ion with m/z 305
3
2
4
The absorption spectra of platinates(IV), differing
only in the nature of the ammonium ligand, are very
similar. Four absorption bands are presented in the
available range (DMF) for (+)ꢀ(bornylNH ) [PtCl ] and
3
2
6
(
(
+)ꢀ(bornylNH ) [PtCl ] complexes, three bands, for
3 2 4
–)ꢀ(menthylNH ) [PtCl ] complex; positions and intenꢀ
3
2
6
+
sities of the bands are typical of the platinum(II) and (IV)
complexes. In the circular dichroism (CD) spectrum of
bornylammonium platinates(II) and (IV), a d—dꢀtransiꢀ
tion for platinum at λ = 388 nm is observed, which
has a weak induced optical activity; for (–)ꢀ(menthylꢀ
NH ) [PtCl ], activity of this band turned out to be below
([Me SiOSi(Me )CH CH Si(Me )OSi(Me )Vin – Me]
2
2
2
2
2
2
+
or [Me SiCH CH Si(Me )OSi(Me )CH CH SiMe ] );
2
2
2
2
2
2
2
2
if only terminal Si—H groups are present, the ion with
+
m/z 293 ([Me SiOSi(Me )CH CH Si(Me )OSiMe ] ) is
2
2
2
2
2
2
the base one). The presence of the fragment with m/z 28,
+
which we assigned to the [CH CH ] ion, serves as the
3
2
6
2
2
the threshold of detection. This results from the fact that
the rigid аsymmetric bornyl framework is the better inꢀ
ductor of optical activity as compared with the conformaꢀ
tionally labile menthyl structure.
Scheme 2
The platinates(II) and (IV) obtained rotate the planeꢀ
polarized light in the same direction as the bornylꢀ and
menthylammonium hydrochlorides. However, the obꢀ
served molar rotation of the platinates is lower than that
of the corresponding hydrochlorides (for example, for
2
0
(
(
bornylNH ) [PtCl ], [Φ]
in DMSO is +70.9°, for
bornylNH ) [PtCl ], +93.6°, and for bornylNH •HCl,
3
2
6
D
3
2
4
2
+
34.5°).
Hydrosilylation of siloxanes. 1,1,3,3ꢀTetramethylꢀ
disiloxane (HMe Si) O and 1,3ꢀdivinylꢀ1,1,3,3ꢀtetraꢀ
2
2
methyldisiloxane (VinMe Si) O (Vin is vinyl) have been
2
2
chosen for the study of comparative catalytic activity of
the obtained metal complexes in the hydrosilylation reacꢀ
tion. Disiloxanes (HMe Si) O and (VinMe Si) O besides
2
2
2
2
the “modeling” of typical processes of solidifying of siloxꢀ
anes by the hydrosilylation reaction, allow one to obtain
siloxane monomers, containing active terminal Si—H or
Si—Vin groups, as well as to synthesize carbosiloxane
linear polymers.
Hydrosilylation in the (HMe Si) O—(VinMe Si) O
2
2
2
2
system with equimolar ratio of the reagents proceeds
with the use of either one or two active groups (Si—H or

Chiral ammonium platinates
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
351
Scheme 3
main criterion allowing us to distinguish a direction of the
addition: it is present when the βꢀaddition occurs, but it is
absent in the αꢀadduct.
increase in the effective positive charge on the silicon
atom of the Si—H group of the monoadducts as comꢀ
1
9
pared with (HMe Si) O, as it is known, should make
2
2
According to the GLC data, an addition of one
difficult their addition to the vinyl group (according to
the quantum chemical calculations for the βꢀadduct, the
charge on the silicon atom is +0.982 as compared to
+0.622 for (HMe Si) O (see Ref. 20)).
(
HMe Si) O molecule initially takes place, predominantly
2 2
giving rise to the βꢀadduct (Scheme 2).
Then, in the presence of all the complexes under
consideration, the formed monoadducts undergo furꢀ
ther rapid transformations, leading mainly to the prodꢀ
ucts of β,βꢀaddition and, to a lesser extent, to the
α,αꢀ and α,βꢀadducts. Formation of the doubleꢀaddition
products with the equimolar ratio of reagents can take
place owing both to the addition of another (HMe Si) O
2
2
The GLC analysis of conversions of the dihydroꢀ and
divinylsiloxanes shows that the conversion of (HMe Si) O
2
2
at least is not lower than the conversion of (VinMe Si) O
2
2
(for example, in the presence of (+)ꢀ(bornylNH ) [PtCl ]
3
2
6
the conversion after 3.5 h is 95 and 88%, whereas in the
presence of (+)ꢀ(bornylNH ) [PtCl ], 66 and 65% for
2
2
3 2
4
molecule to the vinyl group of the monoadduct
Scheme 3; the hydrosilylation of the βꢀadduct is shown
(HMe Si) O and (VinMe Si) O, respectively). Analysis
2 2 2 2
(
of the side processes, occurring during the hydrosilylation,
showed the presence of dehydrocondensation and disproꢀ
portionation of (HMe Si) O, however, according to the
as the example) and to the addition of the siliconꢀhydride
fragment of the monoadduct to another (VinMe Si) O
2
2
2
2
molecule (Scheme 4; see Ref. 18).
When the equimolar ratios of the reagents are used,
both pathways are equally possible, however, a significant
GLC data, consuming of the latter in the side reactions
(for example, in the presence of (+)ꢀ(bornylNH ) [PtCl ])
does not exceed 2% for 3.5 h. A slightly higher conversion
3
2
6
Scheme 4

352
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
de Vekki et al.
of (HMe Si) O (thus, if the consumption of (HMe Si) O
silylation. Products with the terminal Si—H and Si—Vin
groups are presented in the reaction mixture in lower
amounts (according to the chromatography data, the
ratio siloxane with two Si—H groups : siloxanes with
terminal Si—H and Si—Vin groups is 9 : 2).
Kinetic curves of the hydrosilylation catalyzed by
bornylꢀ and menthylammonium platinum complexes are
characterized by an induction period (at the temperature
below 80 °C) (Fig. 1), the presence of which is caused
by the low solubility of these coordinating compounds in
the reaction medium and by the formation of the “true”
catalyst.
2
2
2
2
in the side processes is subtracted, the conversion of
HMe Si) O in the presence of (+)ꢀ(bornylNH ) [PtCl ]
(
2
2
3 2
6
is higher than that of (VinMe Si) O by 5%) allows one to
2
2
assume that the monoadducts are slightly more reactive in
the reaction with (HMe Si) O than with (VinMe Si) O.
2
2
2
2
Analysis of the chromatoꢀmass spectra of the hydroꢀ
silylation products also confirms this assumption, since
H[Me SiOSi(Me )CH CH ] Si(Me )OSi(Me )H siloxane
2
2
2
2 2
2
2
with two terminal Si—H groups (t = 4.8 min) is the main
r
product of the double addition, the scheme of decompoꢀ
1
8
sition of which agrees with that given in the literature.
A prolonged keeping of the reaction mixtures under
consideration ((HMe Si) O, (VinMe Si) O, and bornylꢀ
Catalytic properties of the complexes in the
(HMe Si) O—(VinMe Si) O system significantly depend
2
2
2
2
2
2
2
2
or menthylammonium platinate) is accompanied by disꢀ
appearance from the chromatography chart of signals of
monoꢀ and diaddition products due to the rapid more
on the oxidation state of the complexꢀforming atom and
on the nature of the ammonium counterion. Activity of
the catalysts, evaluated by the time of 50% conversion
of (VinMe Si) O (see Fig. 1, curves 4, 6—8), decreases
“
deep” hydrosilylation, i.e., further mutual addition of
2
2
the monoꢀ and diadducts. Such a behavior of the siloxane
systems is characteristic of hydrosilylation in the presꢀ
in the following sequence: (–)ꢀ(menthylNH ) [PtCl ]
3 2 6
(32 min) > (Et NH) [PtCl ] (120 min) > (+)ꢀ(bornylꢀ
3
2
6
ence of complexes with the outerꢀsphere ammonium
NH ) [PtCl ] (210 min) > (+)ꢀ(bornylNH ) [PtCl ]
3 2 4 3 2 6
ligands;1
2,18
and due to an increase in the molecular
(233 min). The time to reach a complete conversion
of (VinMe Si) O is the shortest in the case of
weights of the siloxanes formed, an increase in the viscosꢀ
ity of the reaction solution is observed (after 25 h in
the presence of (+)ꢀ(bornylNH ) [PtCl ], the viscosity
2
2
(Et NH) [PtCl ] (470 min) and the longest, in the case of
3
2
6
(+)ꢀ(bornylNH ) [PtCl ] (>10 h). Stability of the comꢀ
3
2
4
3 2
4
is 0.34 Pa s). Analysis of the chromatoꢀmass spectra shows
plexes in the reaction medium against decomposition
to platinum metal decreases in the following sequence:
(+)ꢀ(bornylNH ) [PtCl ] >> (+)ꢀ(bornylNH ) [PtCl ] >
that the siloxane with two terminal Si—H groups (t =
r
3
4.0 min), resulted from a sequential β-addition of the
3
2
6
3 2
4
siloxanes, is the main product of the “deep” hydroꢀ
(Et NH) [PtCl ] > (–)ꢀ(menthylNH ) [PtCl ]. Menthylꢀ
3 2 6 3 2 6
ammonium hexachloroplatinate(IV) is reduced to
platinum metal immediately, a decomposition of
Conversion (%)
(
Et NH) [PtCl ] starts in 10 min after the heating began,
4
3 2 6
6
1
2
and (+)ꢀ(bornylNH ) [PtCl ] gives no platinum metal at
3
3 2 6
all during the reaction (visual control). The selectivity of
7
5
8
6
4
2
0
0
0
0
βꢀaddition (determined from the correlation of the CH
2
1
8
and CH groups in the H NMR spectrum) changes in the
3
following sequence: (+)ꢀ(bornylNH ) [PtCl ] (96%) >
3
2
4
(
[
+)ꢀ(bornylNH ) [PtCl ] (93%) ≈ (–)ꢀ(menthylNH ) ꢀ
3 2 6 3 2
PtCl ] (92%).
6
The high stability of the (+)ꢀ(bornylNH ) [PtCl ]
3
2
6
complex against decomposition prompted us to estimate
the possibility of its reuse. It was found that the threeꢀ
time reuse of the catalyst in the (HMe Si) O—
2
2
(
VinMe Si) O system increases its catalytic activity (see
2 2
Fig. 1, curves 2—4). This can be explained by the gradual
increase in the amount of “true” catalyst of hydroꢀ
silylation, which really participates in the formation of
the reaction products.
0
1
00
200
300
400
t/min
Fig. 1. Changes in time of conversion of divinyltetramethylꢀ
disiloxane in the reaction with tetramethyldisiloxane (80 °C,
HMe Si) O : (VinMe Si) O = 1 : 1 (mol.)) in the presence
For the preliminary activation of (+)ꢀ(bornylꢀ
NH ) [PtCl ], i.e., for the possible preparation of the
(
3 2
6
2
2
2
2
“
true” catalyst, we treated it with (HMe Si) O or
of (bornylNH ) [PtCl ] (1—5), (menthylNH ) [PtCl ] (6),
2 2
3
2
6
3 2
6
(
(
Et NH) [PtCl ] (7), and (bornylNH ) [PtCl ] (8) complexes
(VinMe Si) O (80 °C, 5 h). It turned out that the heating
3
2
6
3 2
4
2 2
–
3
–1
C = 1.88•10 mol L ) after treatment with (HMe Si) O (1)
of the complex in (VinMe Si) O leads to a decrease of the
2 2
2
2
and (VinMe Si) O (5), and without treatment (2—4, 6—8).
The catalyst was used 3 (2), 2 (3), and 1 (4) times.
induction period of the reaction with the parallel decrease
in activity of the catalyst (see Fig. 1, curves 4 and 5). At
2
2

Chiral ammonium platinates
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
353
the same time, (+)ꢀ(bornylNH ) [PtCl ] after the reflux
Scheme 5
3
2
6
with (HMe Si) O turned out to be the most active catalyst
2
2
in the siloxane system (see Fig. 1, curve 1), and an
increase in activity of the catalyst causes only a slight
decrease in the selectivity of its action (chromatography
1
data): according to the H NMR data, the share of
βꢀaddition in the hydrosilylation products formed is 92%,
whereas the use of untreated (+)ꢀ(bornylNH ) [PtCl ]
3
2
6
gives 95% of βꢀaddition.
The reaction of (+)ꢀ(bornylNH ) [PtCl ] with
3
2
6
1
(
VinMe Si) O does not change the H NMR spectrum.
2 2
When (HMe Si) O reacts with (+)ꢀ(bornylNH ) [PtCl ],
2
2
3 2
6
signals of the Me groups of such compounds as
H(Me )SiOSiMe (δ 0.06, 0.09, 0.16, and 0.17 (all s))
2
3
and H(Me )SiOSi(Me )OSi(Me )H (δ 0.04 (s) and 0.17
2
2
2
(
d, J = 2.5 Hz)), formed by the disproportionation and
dehydrocondensation of tetramethyldisiloxane, as well as
new signals at δ 0.04, 0.07, 0.12, 0.13, 0.18, and 0.19 are
1
observed in the H NMR spectrum. After 1.5 h, the reacꢀ
tion solution acquires yellow and then, green color. Howꢀ
ever, the isolation and characterization by spectroscopic
methods of the colored compound were unsuccessful:
attempted precipitation or highꢀvacuum lowꢀtemperature
removal of the hydrosiloxanes solution lead to its rapid
decomposition to bornylNH •HCl (NMR data) and,
2
probably, colloidal platinum. The data obtained allow us
to assume that formation of the “true” catalyst of hydroꢀ
silylation occurs, in fact, under action of hydrosiloxane.
Аsymmetric hydrosilylation of acetophenone. Hydroꢀ
silylation of acetophenone with diphenylsilane and
subsequent hydrolysis of obtained silyl ethers 1 is one
of the methods for the synthesis of Sꢀ or Rꢀisomers of
presence of platinum complexes with the innerꢀsphere
ligands was confirmed previously by the chromatoꢀmass
spectrometry.
2
2
1
ꢀphenylethanol 2 and it is widely used for the estimation
of ability of a chiral catalyst to the аsymmetric induction
(
Scheme 5).
Silver tetrafluoroborate or trifluoromethanesulfonate
2
1
are used for the better activation of the hydrosilylation.
Hydrosilylation of acetophenone with diphenylsilane
in the presence of chiral metal complexes under considerꢀ
After 13 days (5 °C), the conversion of acetophenone
1
ation and AgBF proceeds slowly. According to the H
in the presence of (+)ꢀ(bornylNH ) [PtCl ] reaches
4
3
2
6
NMR data, 1ꢀphenylethoxy(diphenyl)silanes 1 (δ 1.62
86.3%, in the presence of (–)ꢀ(menthylNH ) [PtCl ],
3 2 6
(
5
(
d, 3 H, Me, J = 6.4 Hz); 5.12 (q, 1 H, CH, J = 6.4 Hz);
.55 (s, 1 H, SiH)) and 1ꢀphenylvinyloxy(diphenyl)silane
3) (δ 4.87 (d, 1 H, CH , J = 2.2 Hz); 5.04 (d, 1 H, CH ,
73.5%, and in the presence of (+)ꢀ(bornylNH ) [PtCl ],
3 2 4
1
only 52.5%. In this case, the yields of silyl ether 1 ( H
NMR data) were 79.4, 50.9, and 39.9%, of silane 3, 3.0,
8.2, and 5.8%, of 4, 3.9, 14.4, and 6.8% in the presence of
(+)ꢀ(bornylNH ) [PtCl ], (–)ꢀ(menthylNH ) [PtCl ],
2
2
J = 2.3 Hz); 5.74 (s, 1 H, SiH)) are the reaction products,
which was observed previously22 for the hydrosilylation in
the presence of rhodium complexes. In addition, signals
3
2
6
3
2
6
and (+)ꢀ(bornylNH ) [PtCl ], respectively. Thus, (+)ꢀ(borꢀ
3
2
4
at δ 1.50 (d, 1 H, CH , J = 5.4 Hz), 4.87 (dd, 1 H, CH, J
nylNH ) [PtCl ] complex is the most active and
2
3 2 6
=
5.4 Hz, J = 6.7 Hz), 5.68 (s, 1 H, SiH), and 5.78 (s, 1
chemoselective catalyst for the hydrosilylation of acꢀ
etophenone, whereas (+)ꢀ(bornylNH ) [PtCl ] was the
1
H, SiH) are observed in the H NMR spectrum, which we
assigned to 2ꢀphenylethylꢀ2ꢀdiphenylsiloxy(diphenyl)ꢀ
3
2
4
most selective in the hydrosilylation of (VinMe Si) O.
2
2
silane (4) (signal at δ 1.64 (d, 1 H, CH , J = 5.4 Hz) is
Stereoselectivity of hydrosilylation is usually deterꢀ
mined from the structure of 1ꢀphenylethanol, formed by
the hydrolysis of the reaction mixture (after the 100%
conversion of acetophenone is reached). In the presence
2
shielded by the Me group of compound 1). At the same
time, we did not observe an addition product of both SiH
groups of diphenylsilane, the formation of which in the

354
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
de Vekki et al.
from 80 to 200 °C at 10 deg min–1. The sequence of peaks on a
chromatography chart: βꢀ, αꢀ, β,βꢀ, β,αꢀ, and α,αꢀadducts
of bornylammonium catalysts, the subsequent hydrolysis
leads to a chiral 1ꢀphenylethanol in all the cases, the
absolute configuration of which depends on the platiꢀ
num oxidation state: in the presence of (+)ꢀ(bornylꢀ
NH ) [PtCl ], (–)ꢀSꢀ2 (ee 24%) is formed and in the
(
tr = 14, 15, 26, 28, and 29 min, respectively). Assignment of
the GC peaks of the adducts was made based on the data in
Refs 17 and 18.
3
2
6
Hydrosilylation of 1,3ꢀdivinylꢀ1,1,3,3ꢀtetramethyldisiloxane
was performed with equimolar amount of 1,1,3,3ꢀtetramethylꢀ
disiloxane in the presence of the internal standard (octaꢀ
methylcyclotetrasiloxane) in the sealed tubes with subsequent
chromatography of the reaction mixture at arbitrary times.
Concentration of the complexes in the reaction mixture was
presence of (+)ꢀ(bornylNH ) [PtCl ], (+)ꢀRꢀ2 (ee 11%).
3
2
4
The (–)ꢀ(menthylNH ) [PtCl ] complex does not cause
3
2
6
the аsymmetric induction, which, apparently, results from
its rapid and complete decomposition in the reaction
medium to platinum metal.
varied in the range 1•10– —2•10 mol L
4
–3
–1
.
As it is known,23 the highest enantioselectivity of
To recover the catalyst, after 100% conversion of
VinMe Si) O was reached in the preceding cycle, the reaction
hydrosilylation is usually reached by the introduction into
the reaction mixture of 2—13ꢀfold excess of the chiral
ligand relatively to the metal. An excess of the optically
active ligand is especially important when complexes with
(
2
2
mixture was cooled, the undissolved catalyst was filtered off,
washed with dichloromethane, and added to a new reaction
mixture, and the next hydrosilylation cycle was carried out
according to the general procedure.
2
4—26
the nitrogenꢀcontaining chiral ligands are used.
Therefore, we also accomplished a hydrosilylation in the
presence of 10ꢀfold molar excess of the corresponding
hydrochlorides (amines were not used, since they can
enter the inner coordination sphere and thus in situ
change the structure of the complex used). In case of
Hydrosilylation of acetophenone with diphenylsilane was
carried out in THF in the presence of AgBF according to the
4
2
1
known procedure, the course of the reaction was monitored by
NMR. 1ꢀPhenylethanol was isolated by column chromatoꢀ
graphy, ee was determined by polarimeteric method from the
observed angle of rotation of a mixture of enantiomers in toluene.
Commercial (+)ꢀmenthol, ethanol, propanꢀ2ꢀol, toluene,
diethyl ether, acetophenone, THF, DMF, DMSO, octamethylꢀ
cyclotetrasiloxane, and H PtCl •4H O (all of chemically pure
(
+)ꢀ(bornylNH ) [PtCl ] and (–)ꢀ(menthylNH ) [PtCl ],
3 2 4 3 2 6
such an approach did not result in the аsymmetric inducꢀ
tion, whereas in the case of (+)ꢀ(bornylNH ) [PtCl ],
3
2
6
2
6
2
(
+)ꢀRꢀ2 (ee 24%) was the reaction product. Thus, an
grade); 1,3ꢀdivinylꢀ1,1,3,3ꢀtetramethyldisiloxane, 1,1,3,3ꢀtetraꢀ
methyldisiloxane, and AgBF4 (Aldrich); Dꢀ(+)ꢀcamphor
and diphenylsilane (Acros); silica gel 60 (Merck) were used in
the experiments; (Et NH) [PtCl ] was obtained as described
addition of the outerꢀsphere chiral counterion during the
hydrosilylation, catalyzed by (+)ꢀ(bornylNH ) [PtCl ]
3
2
6
complex, leads to the inversion of configuration of
ꢀphenylethanol formed.
3
2
6
in Ref. 12.
1
Chromatoꢀmass spectrometry study of the (HMe Si) O—
2
2
(
VinMe Si) O reaction mixture (8 h, 80 °C, (+)ꢀ(bornylꢀ
2 2
Experimental
NH ) [PtCl ]) was performed on a Agilent 6890N chromatoꢀ
3
2
6
graph with an Agilent 5973N massꢀselective detector and EI
(70 eV) ionization. A DBꢀ5MS quartz capillary column (60 m ×
0.25 mm, the phase film thickness, 0.25 µm) was used; the
injector temperature was 280 °C, the interface temperature was
290 °C, the temperature of the column was varied from 150 to
NMR spectra were recorded on a Bruker АCꢀ200 and Bruker
WMꢀ400 spectrometers in CDCl and (CD ) SO (200.13, 400.14
3
3 2
1
13
(
H), and 50.33 MHz ( C)) with the use of a signal of the
deuterated solvent as the internal standard. IR spectra were
–
1
–1
recorded on a Shimadzu FTIRꢀ8400S (4000—400 cm ) and
280 °C at 10 deg min ; helium was the carrier gas, separation of
–
1
Hitachi FISꢀ3 (400—100 cm ) spectrometers in KBr pellets.
Elemental analysis was performed on a Leco CHNꢀ932 C,H,Nꢀ
analyser. Polarimetric study was carried out on a Perkin—Elmer
the flow, 1 : 20; a sample was 1 µL in volume. Suggested structures
of the adducts, detected by the chromatoꢀmass spectrometry
study, are given below.
2
41MC instrument in quartz thermostated cuvettes of 10 cm in
Adduct
HMe SiOSi(Me )CH CH Si(Me )OSi(Me )ꢀ
2 2 2 2 2 2
length. CD spectra were recorded on a JACSO Jꢀ500
spectrometer (285—700 nm) in DMF with concentration
of 5 mg mL–1. Electronic absorption spectra were obtained
on a Specord Mꢀ40 doubleꢀbeam scanning spectrophotometer
CH=CH . t = 3.3 min, the content in the mixture, 6.2%. MS,
m/z (Irel (%)): 320 [M – H] (4), 305 [M – H – Me] (100), 291
2
r
+
+
+
+
[M – 2 Me] (9), 277 (19), 263 [M – H – 2 Me – Vin] (2), 249
[M – 3 Me – Vin]+ (1), 235 [M – H – SiMe Vin] (2), 219
[M – H – OSiMe Vin] (32), 205 [M – H – SiMe Vin – 2 Me]
(6), 191 [M – 3 Me – SiMe Vin] (9), 175 [Me SiOSiꢀ
2 2
+
2
+
+
(
5
250—900 nm) for solutions in DMF with concentration of
2
2
–
1
+
and 0.5 mg mL
for the visible and near UV regions,
+
respectively. Melting points were determined on the Kofler
heating apparatus with the rate of heating 2.5 deg min–1
(Me )CH CH Si(Me )O – 4 Me] (2), 160 [Me SiOSiMe
2 2 2 2 2
2ꢀ
and/or
+
+
+
.
CH CH ] (5), 145 [Me SiOSi(Me)CH CH ]
2 2 2 2 2
[MeSiOSi(Me )CH CH ] (53), 133 [HMe SiOSiMe ] (9),
117 [Me SiOSiMe] (16), 103 [HMeSiOSiMe] and/or
[HSiOSiMe2] and/or [HMe SiOSi] (2), 85 [SiMe Vin] (4),
+
Viscosimetric study was performed on a Rheotest 2 (VEB MLW)
instrument.
2 2 2 2 2
+
+
2
+
+
+
Chromatographic analysis of hydrosilylation products was
carried out on a Tsvetꢀ100 chromatograph with the katharometer
as the detector on a column (3000×4 mm) with SEꢀ30 (10 wt.%)
on Chromaton NꢀAWꢀDMCS; helium was the carrier gas
2
2
+
+
+
73 [HSiOSi] (30), 59 [OSiMe] (7), 45 [HSiO] (3), 28
+
[CH CH ] (1).
2
2
Adduct
HMe SiOSi(Me )CH(Me)Si(Me )OSi(Me )ꢀ
2 2 2 2
(
4 L h–1), the bridge current was 100 mA. The injector
CH=CH . t = 3.4 min, the content in the mixture, 4.6%. MS,
2
r
+
+
temperature was 300 °C, the column temperature was varied
m/z (Irel (%)): 320 [M – H] (1), 305 [M – H – Me] (100), 291

Chiral ammonium platinates
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
355
+
[
2
(
M – 2 Me]+ (3), 277 (6), 263 [M – H – 2 Me – Vin]+ (2),
[Me SiOSi(Me )CH CH Si(Me )OSi(Me )Vin – Me] and/or
2
2
2
2
2
2
+
+
+
+
47 [M – HSiMe – Me] (1), 231 [M – HMe SiO – Me]
[Me SiCH CH Si(Me )OSi(Me )CH CH SiMe ]
and/or
2
2
2
2
2
2
2
2
2
2
+
2), 219 [M – H – OSiMe Vin] (13), 205 [M – H –
[Me SiCH(Me)Si(Me )OSi(Me )CH CH SiMe ]
(100),
2
2
2
2
2
2
2
+
+
+
SiMe Vin – 2 Me] (4), 191 [M – 3 Me – SiMe Vin] (6),
1
[
and/or [MeSiOSi(Me )CHMe] (6), 133 [HMe SiOSiMe ]
(
[
7
291 [Me SiCH(Me)SiMe OSiMe CH CH SiMe O – 2 Me]
2
2
2 2 2 2 2 2
+
+
77 (2), 159 [M – H – 4 Me – OSiMe Vin] and/or
Me SiOSi(Me )Vin] (2), 145 [Me SiOSi(Me)CHMe]
(10), 277 (8), 263 [MeCHSiMe OSi(Me )CH CH Si(Me )O]
2 2 2 2 2
2
+
+
+
+
and/or [CH CH SiMe OSi(Me )CH CH Si(Me )O] (3), 246
2
2
2
2 2 2 2 2 2 2
+
+
[Me SiCH CH Si(Me OSiMe Vin] (58), 233 [HMe SiOꢀ
2
2
2
2
2
2
2)
2
2
+
+
+
5), 117 [Me SiOSiMe] (4), 103 [HMeSiOSiMe] and/or
HSiOSiMe ] and/or [HMe SiOSi] (1), 85 [SiMe Vin] (3),
3 [HSiOSi] (17), 59 [OSiMe] (5), 45 [HSiO]+ (1).
Si(Me )CH(Me)Si(Me )OSiMe
–
4
Me]
(55), 219
2
2
2
2
+
+
+
+
[Me SiOSi(Me )CH CH SiMe ] (36), 203 [HMe SiOꢀ
2
2
2
2
2
2
2
2
2
+
+
+
Si(Me )CH(Me)Si(Me )OSiMe
– 6 Me]
(10), 191
2
2
2
+
Adduct H[Me SiOSi(Me )CH CH ] Si(Me )OSi(Me )H.
[HMe SiOSi(Me )CH(Me)Si(Me )O – 3 Me] (4), 175
2
2
2
2 2
2
2
2
2
2
+
tr = 4.8 min, the content in the mixture, 1.7%. MS, m/z
(
Si(Me )CH CH ] (100), 279 [M – HSiMe OSi(Me )CH CH –
Me] (5), 263 [M – HMe SiOSi(Me )CH CH – 2 Me – H]
(
[
[
[
[
[Me SiOSi(Me )CH(Me)Si(Me )O
–
4
Me] (4), 159
2
2
2
+
+
+
Irel (%)): 305 [M – 2 HMe SiO] (2), 293 [M – H – HSiMe Oꢀ
[Me SiOSi(Me )Vin] (9), 145 [Me SiOSi(Me)CH CH ]
2
2
2 2 2 2 2
+
+
and/or [MeSiOSi(Me )CH CH ] and/or [Me SiOSi(Me)ꢀ
2
2
2
2
2
2
2
2
2
2
2
+
+
CHMe]+ and/or [MeSiOSi(Me )CHMe]
+
(38), 133
2
2
2
2
2
+
+
+
2), 249 [M – HSiMe OSi(Me )CH CH – 3 Me] (1), 233
[HMe SiOSiMe ] (16), 117 [Me SiOSiMe] (16), 103
2
2
2
2
2
2
2
+
+
+
+
M – HMe SiOSi(Me )CH CH – 4 Me – H] (2), 219
HMe SiOSi(Me )CH CH Si(Me )O]
M – HMe SiOSi(Me )CH CH – 5 Me] (56), 205
M – HSiMe OSiMe CH CH SiMe – H – 2 Me] (17), 191
HMe SiOSi(Me )CH CH Si(Me )O – 2 Me] (7), 177 (3),
[HMeSiOSiMe] and/or [HSiOSiMe ] (2), 85 [SiMe Vin]
2
2
2
2
2
2
+
(10), 73 [HSiOSi] (45), 59 [OSiMe]+ (7), 43 [SiMe]+ (4), 28
+
M
–
and/or
2
2
2
2
2
+
+
+
[CH CH ] , [Si] (14).
2
2
2
2
2 2
+
Adduct H[Me SiOSi(Me )CH CH ] Si(Me )OSi(Me )ꢀ
2 2 2 2 5 2 2
CH=CH . t = 24.5 min, the content in the mixture, 5.6%. MS,
m/z (Irel (%)): 480 [Me SiOSi(Me )CH CH Si(Me )OSi(Me )ꢀ
2 2 2 2 2 2
2
2
2
2
2
+
[
2
2
2
2
2
2 r
+
1
1
1
59 [M – HMe SiOSi(Me )CH CH Si(Me )O – 4 Me] (2),
2
2
2
2
2
+
+
+
47 (29), 133 [HMe SiOSiMe ] (70), 117 [Me SiOSiMe] (12),
CH CH Si(Me )OSiMe Vin] (1), 465 [Me SiOSi(Me )ꢀ
2
2
2
2 2 2 2 2 2
+
+
+
+
03 (3), 85 (2), 73 [HSiOSi] (28), 59 [OSiMe] (6), 45 [HSiO]
CH CH Si(Me )OSi(Me )CH CH Si(Me )OSiMe Vin – Me]
2
2
2
2
2
2
2
2
+
+
(
2), 28 [CH CH ] , [Si] (3).
(3),
451
[Me SiOSi(Me )CH CH Si(Me )OSi(Me )ꢀ
2
2
2 2 2 2 2 2
+
Adduct H[Me SiOSi(Me )CH CH ] Si(Me )OSi(Me )ꢀ
CH CH Si(Me )OSi(Me )CH CH – 2 Me] (1), 393
2
2
2
2
3
2
2
2ꢀ 2 2 2 2 2
CH=CH . t = 12.0 min, the content in the mixture, 7.3%. MS,
[Me SiOꢀSi(Me )CH CH Si(Me )OSi(Me )CH CH Si(Me )ꢀ
2 2 2 2 2 2 2 2 2
2
r
+
+
m/z (Irel (%)): 539 [M – H – OSi(Me )Vin] and/or [M – Vin –
OSiMe2 – 4 Me] (1), 379 [Me SiOSi(Me )CH CH
2
2 2 2 2ꢀ
+
+
+
HMe SiO] (0.5), 481 [M – H – Me SiOSi(Me )Vin] (1), 465
Si(Me )OSi(Me )CH CH Si(Me )] (2), 363 (1), 349 (0.5), 333
2 2 2 2 2
2
2
2
+
+
[
M – HMe SiOSi(Me )CH CH – Me] (4), 451 [M – H –
Me SiOSi(Me )Vin – 2 Me] and/or [M – HMe SiO –
Me SiVin – 2 Me] and/or [M – HMe Si – OSiMe Vin – 2
(1), 320 [Me SiOSi(Me )CH CH Si(Me )OSiMe Vin] (16),
2
2
2
2
2
2
2
2
2
2
+
+
+
305 [Me SiOSi(Me )CH CH Si(Me )OSi(Me )Vin – Me]
and/or [Me SiCH CH Si(Me )OSi(Me )CH CH SiMe ]
2 2 2 2 2 2 2 2
2
2
2
2 2 2 2 2 2
+
2
2
2
+
+
Me] (1), 407 [M – HSiMe OSi(Me )CH CH SiMe – Me]
(80),
291
[Me SiCH CH Si(Me )OSi(Me )CH CH
2
2
2
2
2
2 2 2 2 2 2
2ꢀ
+
(
1), 379 [Me SiOSi(Me )CH CH Si(Me )OSi(Me )CH CH ꢀ
Si(Me )O – 2 Me] (6), 277 (5), 263 [CH CH Si(Me )ꢀ
OSi(Me )CH CH Si(Me )O] (1), 246 [Me SiCH CH ꢀ
Si(Me )OSiMe Vin]
2
2
2
2
2
2
2
2
2
2
2
2
+
+
Si(Me )] (2), 363 (1), 335 (3), 320 [Me SiOSi(Me )CH CH ꢀ
Si(Me )OSi(Me )Vin] (13), 305 [Me SiOSi(Me )CH ꢀ
CH Si(Me )OSi(Me )Vin
CH Si(Me )OSi(Me )CH CH SiMe ]
2
2
2
2
2
2
2
2
2
2
2
2
+
+
(42),
233
4
[HMe SiOSi(Me )ꢀ
2
2
2
2
2
2
2
2
2
+
+
–
Me] and/or [Me SiCH ꢀ
CH CH Si(Me )OSiMe
–
Me]
(100),
219
2
2
2
2
2
2
2
2
2
+
+
(100),
291
[Me SiOSi(Me )CH CH SiMe ] (34), 203 [HMe SiOꢀ
2
2
2
2
2
2
2
2
2
2
2
2
+
+
[
Me SiOSi(Me )CH CH Si(Me )OSi(Me )Vin – 2 Me] (7),
Si(Me )CH CH Si(Me )OSiMe
[HMe SiOSi(Me )CH CH Si(Me )O – 3 Me] (8), 175
–
6
Me]
(10), 191
2
2
2
2
2
2
2
2
2
2
2
+
+
2
(
2
2
77 (6), 263 [CH CH Si(Me )OSi(Me )CH CH Si(Me )O]
1), 247 [CH CH Si(Me )OSi(Me )CH CH SiMe ] (26),
33 [HMe SiOSi(Me )CH CH Si(Me )OSiMe – 4 Me] (55),
19 [Me SiOSi(Me )CH CH SiMe ] (31), 203 [HMe Siꢀ
2
2
2
2
2
2
2
2
2
2
2
2
+
+
[Me SiOSi(Me )CH CH Si(Me )O
–
4
Me] (3), 159
2
2
2
2
2
2
2
2
2
2
2
2
+
+
[Me SiOSi(Me )CH CH Si(Me )
–
4
Me]
(9), 145
2
2
2
2
2
2
2
2
2
2
2
+
+
+
[Me SiOSi(Me)CH CH ] and/or [MeSiOSi(Me )CH CH ]
2
2
2
2
2
2
2 2 2 2 2 2
+
+
+
OSi(Me )CH CH Si(Me )OSiMe
–
6
Me] (8), 191
(55), 133 [HMe SiOSiMe ] (9), 117 [Me SiOSiMe] (13), 97
2 2 2
(2), 85 [Me SiVin] (8), 73 [HSiOSi] (33), 55 [SiVin] (3), 41
[SiCH]+ (2), 28 [CH CH ] , [Si] (4).
2
2
2
2
2
+
+
+
+
[
[
[
HMe SiOSi(Me )CH CH Si(Me )O – 3 Me] (11), 175
2
2
2
2
2
2
+
+
+
Me SiOSi(Me )CH CH Si(Me )O
Me SiOSi(Me )Vin] (6), 145 [Me SiOSi(Me)CH CH ]
–
4
Me] (3), 159
2
2
2
2
2
2 2
+
+
Adduct HMe SiOSi(Me )CH(Me)[Si(Me )OSi(Me )CH ꢀ
2 2 2 2 2
2
2
2
2
2
+
+
and/or [MeSiOSi(Me )CH CH ] (40), 133 [HMe SiOSiMe ]
CH ] Si(Me )OSi(Me )CH=CH . t = 27.1 min, the content
2
2
2
2
2
2 4 2 2 2 r
+
+
(
[
[
10), 117 [Me SiOSiMe] (15), 99 [SiCH CH SiMe] (1), 85
Me SiVin] (6), 73 [HSiOSi] (35), 59 [OSiMe] and/or
in the mixture, 2.0%. MS, m/z (Irel (%)): 536
2
2
2
+
+
+
[Me SiCH CH Si(Me )OSi(Me )CH CH Si(Me )OSi(Me )ꢀ
2
2
2
2
2
2
2
2
2
2
+
+
+
+
HMe Si] (3), 28 [CH CH ] , [Si] (2).
CH CH Si(Me )OSiMe Vin – 2 Me] (1), 512 (1), 479
2
2
2
2 2 2 2
Adduct HMe SiOSi(Me )CH(Me)[Si(Me )OSi(Me )CH ꢀ
[HMe SiOSi(Me )CH(Me)Si(Me )OSi(Me )CH CH Si(Me )ꢀ
2 2 2 2 2 2 2
2
2
2
2
2
+
CH ] Si(Me )OSi(Me )CH=CH . t = 12.9 min, the content in
OSi(Me )CH CH Si(Me )OSi(Me ) – 9 Me] (2), 465
2
2
2
2
2
r
2 2 2 2 2
+
the mixture, 1.7%. MS, m/z (Irel (%)): 479 [M – 9 Me – Vin]
2), 465 [M – HMe SiOSi(Me )CHMe – Me] (7), 451 [M –
H – 2 Me – Me SiOSi(Me )Vin] and/or [M – HMe SiO –
[Me SiOSi(Me )CH CH Si(Me )OSi(Me )CH CH Si(Me )ꢀ
2 2 2 2 2 2 2 2 2
+
+
(
OSiMe Vin – Me] (3), 451 [Me SiOSi(Me )CH CH Si(Me )ꢀ
2
2
2
2
2
2
2
2
+
+
OSi(Me )CH CH Si(Me )OSi(Me )CH CH
–
2
Me]
2
2
2
2
2
2
2
2
2
2
+
Me SiVin – 2 Me] and/or [M – HMe Si – OSiMe Vin – 2
and/or
[Me SiOSi(Me )CH(Me)Si(Me )OSi(Me )CH ꢀ
2
2
2
2 2 2 2 2
+
+
CH Si(Me )OSi(Me )CH CH – 2 Me]+ (1), 414 (1), 406
Me] (2), 407 [M – Me – HSiMe OSi(Me )CH(Me)SiMe ]
2
2
2
2
2
2
2
2
+
(
2), 393 (3), 379 [Me SiOSi(Me )CH(Me)Si(Me )ꢀ
[Me SiCH CH Si(Me )OSi(Me )CH CH Si(Me )OSiMe Vin]
2
2
2
2 2 2 2 2 2 2 2 2
+
OSi(Me )CH CH SiMe ] (4), 365 (2), 349 (2), 333 (5), 319
Me SiOSi(Me )CH CH Si(Me )OSiMe Vin]
(3), 393 [Me SiOSi(Me )CH CH Si(Me )OSi(Me )CH CH ꢀ
2
2
2
2
2
2
4
2
2
2
2
2
2
+
+
[
(11), 305
Si(Me )OSiMe
–
Me]
(9), 379 [Me SiOꢀ
2
2
2
2
2
2
2
2
2

356
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
de Vekki et al.
+
Si(Me )CH(Me)Si(Me )OSi(Me )CH CH Si(Me )] and/or
[
(1R)ꢀ(–)ꢀMenthylamine hydrochloride. A mixture of
(–)ꢀmenthylamine (0.5 g) and 0.1 M hydrochloric acid (10 mL) was
kept for 0.5 h and the solution was concentrated by the air flow
to 2 mL. A precipitate formed was filtered off and dried in air to
2
2
2
2
2
2
+
Me SiOSi(Me )CH CH Si(Me )OSi(Me )CH CH Si(Me )]
2 2 2 2 2 2 2 2 2
(
4), 356 (3), 333 (4), 319 (11), 305 [Me SiOSi(Me )CH ꢀ
CH Si(Me )OSi(Me )Vin – Me] and/or [Me SiCH CH ꢀ
Si(Me )OSi(Me )CH CH SiMe ] and/or [Me SiCH(Me)ꢀ
Si(Me )OSi(Me )CH CH SiMe ] (68), 291 [Me SiCH CH ꢀ
2
2
2
+
2
2
2
2
2
2
2
0
+
obtain a white substance (0.57 g, 92%), [α]
–27.1 (c 0.15,
2
2
2
2
2
2
D
2
0
i
+
EtOH) (cf. Ref. 28: [α]D –38 (Pr OH)), m.p. 288—289 °C
2
2
2
2
2
2
2
2
+
1
13
Si(Me )OSi(Me )CH CH Si(Me )O
[
–
2
Me]
and/or
(cf. Ref. 32: m.p. 289.5—291 °C). H and C spectra in CDCl
3
2
2
2
2
2
+
28
–1
Me SiCH(Me)Si(Me )OSi(Me )CH CH Si(Me )O – 2 Me]
7), 277 (7), 263 [CH CH Si(Me )OSi(Me )CH CH ꢀ
correspond to the literature data. IR, ν(δ)/cm : 3203
2
2
2
2
2
2
(
(ν(N—H), δ(N—H)); 3033, 2960, 2932 sh, 2874, 2800 sh
2
2
2
2
2
2
+
(
ν(N—H), ν(C—H)); 1605 (δ (N—H)); 1516, 1504 (δ (N—H));
Si(Me )O]
and/or
[MeCHSi(Me )OSi(Me )CH ꢀ
as s
2
2 2 2
+
460 (δ(C—H) ring); 1392 (δ(NC—H)); 1369 (δ(C—H)); 1337
1
CH Si(Me )O] and/or [CH CH Si(Me )OSi(Me )CH(Me)ꢀ
Si(Me )O] (3), 246 [Me SiCH CH Si(Me )OSiMe Vin]
100), 233 [HMe SiOSi(Me )CH(Me)Si(Me )OSiMe – 4 Me]
2
2
2
2
2
2
+
+
(δ(C—H) ring); 1298 (δ(C—H)); 1250 (δ(C—H) ring); 1184,
1170, 1108 (ν(C—C), δ(C—H)); 1087 (ν(C—N)); 1017, 977
(ν(C—C), δ(C—H)); 956 (ν(C—C)); 926 (δ(C—H)); 872, 842,
766 (ν(C—C), δ(C—H)).
2
2
2
2
2
2
+
(
(
[
[
[
[
[
[
2 2 2 2
[Me SiOSi(Me )CH CH SiMe ]
Me SiOSi(Me )CH(Me)SiMe ]
+
79),
219
and/or
2
2
2
2
2
+
(45), 207 (18), 203
HMe SiOSi(Me )CH(Me)Si(Me )OSiMe – 6 Me] (13), 191
2
2
2
+
(1R)ꢀ(+)ꢀBornylamine hydrochloride.
A
mixture of
2
2
2
2
+
(+)ꢀbornylamine (0.9 g) and 0.1 M hydrochloric acid (10 mL)
was kept for 0.5 h and the solution was concentrated by the air
HMe SiOSi(Me )CH(Me)Si(Me )O – 3 Me] (14), 175
2
2
2
Me]+ and/or
Me]+ (5), 159
+
Me SiOSi(Me )CH CH Si(Me )O
Me SiOSi(Me )CH(Me)Si(Me )O
–
– 4
4
2
2
2
2
2
flow to 1 mL. A precipitate formed was filtered off and dried in
2
2
2
20
+
air to obtain a white substance (0.97 g, 87%), [α]
+12.7
Me SiOSi(Me )Vin] (13), 145 [Me SiOSi(Me)CH CH ]
D
2
2
2
2
2
20
13
+
+
+
+
(c 0.15, EtOH), [α]D +18.2 (c 0.1, DMSO). C NMR
(CDCl ), δ: 12.7 (CH ); 17.7, 18.7 (CH CCH ); 26.8 (CH );
and/or [MeSiOSi(Me )CH CH ] , [Me SiOSi(Me)CHMe]
and/or [MeSiOSi(Me )CHMe] (65), 133 [HMe SiOSiMe ]
2
2
2
2
+
3
3
3
3
2
2
2
2
+
33.5 (CH CHN); 43.8 (CH CHCH ); 47.8 (CH CCH );
(
(
[
17), 117 [Me SiOSiMe] (21), 109 (6), 95 (10), 85 [Me SiVin]
2 2 2 3 3
2
2
–1
+
+
+
48.2 (CH CCH ); 56.4 (NCH). IR, ν(δ)/cm : 3190 sh, 2985,
3 2
16), 73 [HSiOSi] (45), 55 [SiVin] (16), 43 [SiMe] (10), 28
+
+
2952 (ν(N—H), ν(C—H)); 1600 (δ (N—H)); 1525, 1512
CH CH ] , [Si] (22).
as
2
2
(
(
(
δs(N—H)); 1495, 1485, 1476, 1459 (δ(C—H) ring); 1410
δ(NC—H)); 1392 (δ(C—H)); 1368 (δ(C—H) ring); 1310
δ(C—H)); 1279, 1251, 1177, 1162, 1152 (ν(C—C), δ(C—H));
Adduct H[Me SiOSi(Me )CH CH ] Si(Me )OSi(Me )H.
tr = 34.0 min, the content in the mixture, 55.7%. MS, m/z
Irel (%)): 480 [HSiMe OSiMe CH CH SiMe OSiMe ꢀ
2
2
2
2 6
2
2
(
2
2
2
2
2
2
1
084 (ν(C—N)); 1043, 1024, 1004 (ν(C—C), δ(C—H)); 942
ν(C—C)); 927 (δ(C—H)); 875, 825, 762 (ν(C—C), δ(C—H)).
Found (%): C, 63.31; H, 10.63; N, 7.38. C H ClN. Calculated
+
CH CH SiMe OSiMe CH CH SiMe – 4 Me] (1), 379
2
2
2
2
2
2
2
(
+
[
Me SiOSi(Me )CH CH Si(Me )OSi(Me )CH CH Si(Me )]
2 2 2 2 2 2 2 2 2
10
20
(
1), 319 [SiMe CH CH SiMe OSiMe CH CH SiMe Oꢀ
SiMe2 – 4 Me]+ (1), 305 [Me SiCH CH Si(Me )OSi(Me )ꢀ
2
2
2
2
2
2
2
2
(
%): C, 63.30; H, 10.62; N, 7.39.
1R)ꢀ(–)ꢀMenthylammonium
Solutions of H PtCl •4H O (187 mg) in Pr OH (3 mL) and
2
2
2
2
2
(
hexachloroplatinate(VI).
+
CH CH SiMe ]
(12), 293 [Me SiOSi(Me )CH CH ꢀ
i
2
2
2
2 2 2 2
+
2
6
2
Si(Me )OSiMe ]
(100), 277 (3), 261 (1), 247
i
2
2
(–)ꢀmenthylammonium hydrochloride (244 mg) in Pr OH
(2 mL) were mixed up, after 10 min, diethyl ether (10 mL) was
added to the mixture. A precipitate formed was immediately
+
[
[
[
[
[
[
[
(
[
[
CH CH Si(Me )ꢀOSi(Me )CH CH SiMe ]
(3),
233
2
2
2
2
2
2
2
+
HMe SiOSi(Me )CH CH Si(Me )OSiMe – 4 Me] (31), 219
2
2
2
2
2
2
+
Me SiOSi(Me )CH CH SiMe ]
(82), 207 (5), 191
HMe SiOSi(Me )CH CH Si(Me )O – 3 Me] (4), 175
i
2
2
2
2
2
filtered off, washed on the filter sequentially with Pr OH (5 mL)
+
2
2
2
2
2
and diethyl ether to obtain an orange complex (220.6 mg, 67%),
+
Me SiOSi(Me )CH CH Si(Me )O
–
4
Me] (1), 159
20
2
2
2
2
2
[α]D –17.6 (c 0.05, DMSO), m.p. 206 °C (with decomp.).
+
Me SiOSi(Me )CH CH SiMe
–
4
Me]
(3), 145
–1
–1
2
2
2
2
2
CD, λ/nm (∆ε/L mol cm ): 333 (–0.010), 327 (+0.022).
+
+
Me SiOSi(Me)CH CH ] and/or [MeSiOSi(Me )CH CH ]
1
2
2
2
2
2
2
H NMR ((CD ) SO), δ: 0.72, 0.85, 0.89 (all d, 3 H each,
+
+
3 2
34), 133 [HMe SiOSiMe ] (21), 117 [MeSiOSiMe ] (7), 86
2
2
2
CHCH , CH CHCH , CH CHCH , J = 6.7 Hz); 1.05 (q, 2 H,
+
+
+
3
3
3
3
3
Me SiCH CH ] (2), 73 [HSiOSi] (16), 59 [OSiMe] (1), 28
2
2
2
CH , J = 7.8 Hz, J = 6.4 Hz); 1.28 (t, 2 H, CH , J = 11.3 Hz);
+
2
2
CH CH ] (1).
2
2
1.39 (m, 1 H, CHCH ); 1.64 (t, 2 H, CHCH CH, J = 8.0 Hz);
3 2
(
1R)ꢀ(–)ꢀMenthylamine. The product was synthesized from
+)ꢀmenthol according to the known procedure, the yield was
1
7
.93 (t, 1 H, CH CHCH , J = 11.2 Hz); 2.89 (m, 1 H, NCH);
3 3
2
7
(
3
–1
–1
.85 (br.s, 3 H, NH ). UV, λ/nm (ε/L mol cm ): 371 (371),
3
20
1
8%, [α]D –24.0 (neat). H NMR spectrum (CDCl ) agrees
–1
3
475 (43), 880 (5). IR, ν(δ)/cm : 3176 (ν(N—H)); 3031, 2957,
2
8 13
with the literature data.
C NMR (CDCl ), δ: 14.6 (CHCH );
3 3
2929 sh, 2871 sh (ν(N—H), ν(C—H)); 1604 (δ (N—H)); 1503,
as
2
0.5, 21.5 (CH CHCH ); 22.4 (CH CH CH); 25.1
CH CHCH ); 31.2 (CHCH ); 34.1 (CH CH CH); 44.7
3 3 2 2
1495 (δ (N—H)); 1460, 1454 (δ(C—H) ring); 1389 (δ(NC—H));
s
(
(
1
369 (δ(C—H)); 1352 (δ(C—H) ring); 1284, 1250 (δ(C—H));
3 3 3 2 2
–
1
CH CHN); 49.6 (NCH); 50.7 (CH CHCH).
1123, 1109 (ν(C—C), δ(C—H)); 953 (ν(C—C)). IR, ν/cm :
2
2
(
1R)ꢀ(+)ꢀBornylamine. The product was obtained from (+)ꢀ
330 (Pt—Cl); 265, 205. Found (%): C, 33.36; H, 6.18; N, 3.89.
C H Cl N Pt. Calculated (%): C, 33.35; H, 6.16; N, 3.89.
2
9
camphor according to the known procedure, the yield was
7%, [α]D +22.9 (c 0.2, EtOH); +32.6 (c 0.1, CHCl3)
cf. Ref. 30: [α ] 20 +22.7 (EtOH)), m.p. 159—160 °C
cf. Ref. 31: m.p. 158—160 °C; cf. Ref. 29: m.p. 162.5—164 °C).
H NMR spectrum (CDCl ) agrees with the literature data.
C NMR (CDCl ), δ: 13.0 (CH ); 18.1, 19.9 (CH CCH );
6.2 (CH ); 28.0 (CH ); 38.2 (CH CHN); 44.6 (CH CHCH );
8.0 (CH CCH ); 48.6 (CH CCH ); 56.3 (NCH).
2
0
44
6
2
2
0
2
(
(1R)ꢀ(+)ꢀBornylammonium hexachloroplatinate(VI). Solutions
i
of H PtCl •4H O (212 mg) in Pr OH (5 mL) and (+)ꢀbornylꢀ
D
2 6 2
i
(
ammonium hydrochloride (220 mg) in Pr OH (5 mL) were mixed
up. A precipitate immediately formed was filtered off, washed
on the filter sequentially with Pr OH (5 mL) and diethyl ether to
obtain a yellow complex (280 mg, 74%), [α] +9.9 (c 0.05,
DMSO), [α]D +12.7 (c 0.05, DMF), m.p. 240 °C (decomp.).
1
29
3
13
i
3
3
3
3
2
0
2
4
2
2
2
2
2
D
2
0
3
3
3
2

Chiral ammonium platinates
Russ.Chem.Bull., Int.Ed., Vol. 57, No. 2, February, 2008
357
CD, λ/nm (∆ε/L mol cm–1): 388 (+0.020), 343 (+0.034).
–
1
8. X. Wang, H. Chakrapani, J. W. Madine, M. A. Keyerleber,
R. A. Widenhoefer, J. Org. Chem., 2002, 67, 2778.
9. A. Sato, H. Kinoshita, H. Shinokubo, K. Oshima, Org. Lett.,
2004, 6, 2217.
10. S. DíezꢀGonzález, N. M. Scott, S. P. Nolan, Organometalꢀ
lics, 2006, 25, 2355.
11. S. Burling, L. D. Field, B. A. Messerle, Organometallics,
2000, 19, 87.
12. D. A. de Vekki, V. N. Spevak, E. A. Kuchaev, N. K.
Skvortsov, Zh. Obshch. Khim., 2005, 75, 1840 [Russ. J. Gen.
Chem., 2005, 75, 1757 (Engl. Transl.)].
1
H NMR ((CD ) SO), δ: 0.83 (s, 6 H, CH CCH ); 0.83 (s, 3 H,
CH ); 1.02 (dd, 1 H, CH , J = 4.0 Hz, J = 14.0 Hz); 1.28 (d,
3
2
3
3
3
2
1
2
H, CH , J = 7.3 Hz); 1.44 (m, 2 H, CH ); 1.66 (m, 2 H, CH );
2
2
2
.15 (dt, 1 H, CH, J = 7.2 Hz, J = 11.4 Hz); 3.27 (m, 1 H,
CHN); 7.74 (br.s, 3 H, NH ). UV, λ/nm (ε/L mol cm ):
72 (26060), 370 (505), 470 (56), 880 (5). IR, ν(δ)/cm : 3185
ν(N—H)); 3137, 3103 sh, 2988 sh, 2954, 2888 sh (ν(N—H),
ν(C—H)); 1591 (δ (N—H)); 1496 (δ (N—H)); 1481, 1473,
–
1
–1
3
–
1
2
(
as
s
1
(
460 (δ(C—H) ring); 1391 (δ(NC—H)); 1368 (δ(C—H)); 1315
δ(C—H) ring); 1300, 1282, 1208, 1197, 1162, 1137 (δ(C—H));
1
9
3
082 (ν(C—N)); 1067, 1032, 1017, 998 (ν(C—C), δ(C—H));
42 (ν(C—C)); 874, 822, 757 (ν(C—C), δ(C—H)). IR, ν/cm–1
33 (Pt—Cl); 240, 195. Found (%): C, 33.53; H, 5.65; N, 3.90.
13. A. V. Gorshkov, V. M. Kopylov, L. Z. Khazen, A. A.
Dontsov, Kauchuk i rezina [Caoutchouc and Rubber], 1989,
25 (in Russian).
:
C H Cl N Pt. Calculated (%): C, 33.53; H, 5.63; N, 3.91.
14. V. M. Kopylov, T. G. Kovyazina, T. M. Buslaeva, N. M.
Synitsyn, V. V. Kireev, A. V. Gorshkov, Zh. Obshch. Khim.,
1987, 57, 1117 [J. Gen. Chem. USSR, 1987, 57, 1103 (Engl.
Transl.)].
2
0
40
6
2
(1R)ꢀ(+)ꢀBornylammonium tetrachloroplatinate(II). A mixture
of (+)ꢀ(bornylNH ) [PtCl ] (145.35 mg) in H O (50 mL) and
3
2
6
2
N H •2HCl (10.65 mg) in H O (5 mL) was heated in a boiling
2
4
2
water bath and the solvent was evaporated by the air flow to
obtain a reddish orange complex (130.96 mg, 88%), [α]D +14.5
15. D. A. de Vekki, N. K. Skvortsov, V. N. Spevak, Tez. dokl. XX
Mezhdunar. Chugaevskoi konf. po koord. khimii [Abstracts of
the XX Int. Chugaev Conf. Coord. Chem.] (June 25—29, 2001),
Rostov Univ. Publ, RostovꢀonꢀDon, 2001, 201 (in Russian).
16. N. G. Klyuchnikov, Rukovodstvo po neorganicheskomu sintezu
[Handbook on Inorganic Synthesis], Khimiya, Moscow, 1965,
391 pp. (in Russian).
17. D. A. de Vekki, V. A. Ol´sheev, V. N. Spevak, N. K.
Skvortsov, Zh. Obshch. Khim., 2001, 71, 2017 [Russ. J. Gen.
Chem., 2001, 71, 1912 (Engl. Transl.)].
2
0
(
(
(
c 0.05, DMSO), m.p. 268—269 °C (decomp.). CD, λ/nm
∆ε/L mol–1 cm ): 388 (+0.016), 286 (–0.032). 1H NMR
(CD ) SO), δ: 0.82 (s, 3 H, CH CCH ); 0.83 (s, 3 H, CH CCH );
–1
3
2
3
3
3
3
0
1
1
.87 (s, 3 H, CCH ); 1.03 (dd, 1 H, CH , J = 4.0 Hz, J = 14.0 Hz);
3
2
.31 (m, 1 H, CH ); 1.53 (t, 2 H, CH , J = 10.1 Hz); 1.65 (br.d,
2
2
H each, CH , J = 4.2 Hz); 2.15 (dt, 1 H, CH, J = 3.2 Hz,
2
J = 10.8 Hz); 3.23 (m, 1 H, CHN); 7.93 (m, 3 H, NH ).
3
–
1
–1
UV, λ/nm (ε/L mol cm ): 272 (2270), 396 (486), 490 (22),
80 (8). IR, ν/cm : 3166 sh (ν(N—H)); 3122, 2985 sh, 2953,
893 sh (ν(N—H), ν(C—H)); 1584 (δ (N—H)); 1504, 1501
–
1
8
2
1
8. D. A. de Vekki, I. V. Viktorovskii, N. K. Skvortsov, Zh.
Obshch. Khim., 2004, 74, 1426 [Russ. J. Gen. Chem., 2004,
74, 1321 (Engl. Transl.)].
as
(
(
δs(N—H)); 1460 (δ(C—H) ring); 1390 (δ(NC—H)); 1369
δ(C—H)); 1315 (δ(C—H) ring); 1299, 1162, 1136 (δ(C—H));
1
2
2
2
9. A. N. Egorochkin, Usp. Khim., 1992, 61, 1092 [Russ. Chem.
Rev., 1992, 61, 600 (Engl. Transl.)].
0. V. V. Zuev, D. A. de Vekki, Phosphorus, Sulfur, Silicon,
Relat. Elem., 2005, 180, 2071.
1. H. Nishiyama, M. Kondo, T. Nakamura, K. Itoh, Organoꢀ
metallics, 1991, 10, 500.
2. A. N. Reznikov, V. I. Lobadyuk, V. N. Spevak, N. K.
Skvortsov, Zh. Obshch. Khim., 1998, 68, 960 [Russ. J. Gen.
Chem., 1998, 68, 910 (Engl. Transl.)].
1
083 (ν(C—N)); 1067, 1037, 1020, 998, 883, 760, 516
ν(C—C), δ(C—H)). Found (%): C, 37.23; H, 6.28; N, 4.33.
C H Cl N Pt. Calculated (%): C, 37.22; H, 6.25; N, 4.34.
(
2
0
40
4
2
This work was financially supported by the Russian
Federation President Council for Grants (Program for
the State Support of Young Scientists of the RF, Grant
MKꢀ3204.2005.3), by the Russian Foundation for Basic
Research (Project Nos 04ꢀ03ꢀ32632а and 06ꢀ03ꢀ32137а),
and the St. Petersburg Government (Grant PD05ꢀ1.3ꢀ20).
2
2
2
3. V. A. Pavlov, Usp. Khim., 2001, 70, 1175 [Russ. Chem. Rev.,
2
001, 70, 1037 (Engl. Transl.)].
4. H. Brunner, R. Becker, G. Riepl, Organometallics, 1984, 3,
354.
5. H. Brunner, A. Kürzinger, J. Organomet. Chem., 1988, 346,
13.
1
References
4
2
2
2
6. H. Brunner, U. Obermann, Chem. Ber., 1989, 122, 499.
7. O. Wallah, Justus Liebigs Ann. Chem., 1893, 276, 296.
8. M. C. Schopohl, K. Bergander, O. Kataeva, R. Froehlich,
S. R. Waldvogel, Synthesis, 2003, 2689.
1
2
. R. Noyori, Asymmetric Catalysis in Organic Synthesis, J. Wiley
and Sons, New York—Chichester—Brisbane—Toronto—
Singapore, 1994, 380 pp.
. R. H. Crabtree, The Organometallic Chemistry of the Transiꢀ
tion Metals, J. Wiley and Sons, USA, 2005, 546 pp.
. H. A. McManus, P. J. Guiry, Chem. Rev., 2004, 104, 4151.
. J. Lacour, V. HebbeꢀViton, Chem. Soc. Rev., 2003, 32, 373.
. M. Basato, A. Biffis, G. Martinati, M. Zecca, P. Ganis, F.
Benetollo, L. A. Aronica, A. M. Caporusso, Organometallics,
2
3
9. R. M. Carman, K. L. Greenfield, Aust. J. Chem., 1984, 37,
1
785.
0. S. A. Kozhin, P. R. Aier, S. V. Vitman, Zh. Org. Khim., 1975,
1, 1640 [J. Org. Chem. USSR, 1975, 11, 1628 (Engl.
3
4
5
1
Transl.)].
3
3
1. J. Houben, Die Metoden der organischen Chemie, Verlag
Georg THIEME, Leipzig, 1935, 4.
2. H. de Botton, Bull. Soc. Chim. Fr., 1959, 1343.
2
004, 23, 1947.
. D. B. Llewellyn, B. A. Arndtsen, Organometallics, 2004, 23,
838.
6
7
2
. L. W. Chung, Y.ꢀD. Wu, B. M. Trost, Z. T. Ball, J. Am.
Chem. Soc., 2003, 125, 11578.
Received April 18, 2006;
in revised form October 29, 2007