Reactions of tertiary alcohols with palladium(II) tetraaqua complex. Formation of palladium π-allyl complexes

Article abstract of DOI:10.1023/A:1013244222139

Transformations of 2-methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-cyclohexanol, and 1-ethyl-1-cyclohexanol in the presence of tetraaquapalladium(II) ions in perchloric acid madium were studied. It was found that the reactions give rise to palladium(II) π-allyl complexes. The reaction rate increases and the yield of the corresponding π-allyl complex decreases with increasing hydrocarbon chain length. Addition of iron(III) ions to the systems essentially increases the yield of palladium π-allyl complexes. The olefin formed from the corresponding tertiary alcohol participates in the formation of the palladium π-allyl complex. Oxidation of 2-methyl-2-butanol with tetraaquapalladium(II) ions gives the isomeric palladium π-allyl complexes [Pd(η³-(CH₃)₂CCHCH₂)bpy]ClO ₄ and [Pd(η³-(CH₂C(CH₃)CHCH ₃))bpy]ClO₄, which were isolated using 2,2'-bipyridyl and characterized by ¹H and ¹³C NMR spectroscopy.

Full text of DOI:10.1023/A:1013244222139

Russian Journal of General Chemistry, Vol. 71, No. 8, 2001, pp. 1169 1175. Translated from Zhurnal Obshchei Khimii, Vol. 71, No. 8, 2001,
pp. 1242 1248.
Original Russian Text Copyright
2001 by V.V. Potekhin, Ryadinskaya, V.M. Potekhin.
Reactions of Tertiary Alcohols with Palladium(II) Tetraaqua
Complex. Formation of Palladium -Allyl Complexes
V. V. Potekhin, N. Yu. Ryadinskaya, and V. M. Potekhin
St. Petersburg State Institute of Technology, St. Petersburg, Russia
Received March 14, 2000
Abstract Transformations of 2-methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-
cyclohexanol, and 1-ethyl-1-cyclohexanol in the presence of tetraaquapalladium(II) ions in perchloric acid
madium were studied. It was found that the reactions give rise to palladium(II) -allyl complexes. The reac-
tion rate increases and the yield of the corresponding -allyl complex decreases with increasing hydrocarbon
chain length. Addition of iron(III) ions to the systems essentially increases the yield of palladium -allyl com-
plexes. The olefin formed from the corresponding tertiary alcohol participates in the formation of the palla-
dium -allyl complex. Oxidation of 2-methyl-2-butanol with tetraaquapalladium(II) ions gives the isomeric
palladium -allyl complexes [Pd( 3-(CH3)2CCHCH2)bpy]ClO4 and [Pd( 3-(CH2C(CH3)CHCH3))bpy]ClO4,
which were isolated using 2,2 -bipyridyl and characterized by 1H and 13C NMR spectroscopy.
Earlier we studied transformations of 2-methyl-2-
propanol in its reaction with the complex [Pd(H2O)4]
(ClO4)2 (I) in perchloric acid in the range 45 75 C
[1]. The major reaction product was a palladium
methallyl complex. On the basis of kinetic regularities
of the process we assumed that the reaction proceeds
through intermediate formation of 2-methylpropene.
Other saturated tertiary alcohols could also be
assumed to transform to the corresponding isomeric
palladium -allyl complexes. To check this assump-
tion, we studied in this work transformations of
2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-
cyclohexanol, and 1-ethyl-1-cyclohexanol in their
reactions with complex I in perchloric acid medium.
in acidic media to form olefins. To confirm the fact
that palladium -allyl complexes originate from
olefins formed by dehydration of tertiary alcohols in
the reaction solution, we studied the reactions by
NMR spectroscopy and iodometry.
1
Analysis of the H NMR spectra showed that se-
condary (internal) olefins are formed selectively from
the corresponding tertiary alcohols in the presence of
complex I: 2-methyl-2-butene from 2-methyl-2-bu-
tanol, 2-methyl-2-pentene from 2-methyl-2-pentanol,
1-methyl-1-cyclohexene
from
1-methyl-1-cyclo-
hexanol, and 1-ethyl-1-cyclohexene from 1-ethyl-1-
cyclohexanol.
Changes in the concentration of olefin in the course
of reaction between tertiary alcohol and complex I
were estimated by iodometry. It is necessary to note
that the rates of olefin formation we impossible to
determine because of the lack of data on equilibrium
constants of dehydration of alcohols under our ex-
perimental conditions. Therefore, the kinetic curves
given in Figs. 1 and 2 relate to olefin accumulation
both in the presence of complex I and without it.
The reactions were carried out at the following
initial concentrations of the reagents, M: complex I
3
5.7 10 , perchloric acid 0.53 0.63, and alcohol 0.1
(except for 1-ethyl-1-cyclohexanol whose concentra-
tion did not exceed 0.05 M because of its restricted
solubility in water).
The formation of palladium(II) -allyl complex can
be detected by the appearance of a characteristic ab-
sorption band at 320 nm in the UV spectrum (extinc-
tion coefficient log 3) [2]. We observed these bands
in all the UV spectra measured in the course of the
reactions of the tertiary alcohols under study with
complex I, which gave grouds to conclude that the
reactions actually give palladium -allyl complexes.
As seen from Fig. 1, curve 1, and Fig. 2, curve 2,
in the absence of palladium olefin is accumulated at a
constant rate from the very beginning of the reaction.
At the same time, in the presence of complex I olefin
either was not detected within a certain period (with
2-methyl-2-propanol; see Fig. 1, curve 3) or its
content was insignificant (with 1-methyl-1-cyclohexa-
nol; see Fig. 2, curve 3). The appearance of this
period is attributable to a high rate of olefin consump-
Palladium -allyl complexes are usually formed
by reactions of olefins with palladium(II) compounds.
Tertiary alcohols are known to be readily dehydrated
1070-3632/01/7108-1169$25.00 2001 MAIK Nauka/Interperiodica

1170
POTEKHIN et al.
30
6
5
5
4
2
2
1
25
20
1
4
3
4
3
3
2
1
15
10
5
3
2
1
0
0
50 100 150 200 250 300 350
Time, min
50 100 150 200 250 300 350
Time, min
Fig. 2. Plot of the concentrations of complex I (C
)
Pd
and olefin (C ) vs. time for the reaction with 1-methyl-
Ol
Fig. 1. Plots of the concentration of complex I (C
)
1-cyclohexanol. C
0.1 M, C
0.63 M, and C
Pd
alc
HClO4 Pd
3
and olefin (C ) vs. time for the reaction with 2-methyl-
5.5 10
M, 40 C. (1) Consumption of complex I,
Ol
2-propanol. C
0.1 M,
C
0.5 M, and C
(2) accumulation of 1-methyl-1-cyclohexene in the
absence of complex I, (3) accumulation of 1-methyl-1-
cyclohexene in the presence of complex I, and (4) ac-
cumulation of 1-methyl-1-cyclohexene in the presence
of complex I and Fe(III).
alc
HClO4
Pd
0.0057 M, 55 C. (1) Consumption of complex I, (2) ac-
cumulation of 2-methylpropene in the absence of com-
plex I, and (3) accumulation of 2-methylpropene in the
presence of complex I.
tion in reaction with palladium(II), and its duration
depended on the rate of consumption of tetraaquapal-
ladium(II) ions. As the concentration of complex I
decreased (Fig. 1, curve 1, and Fig. 2, curve 2), the
rate of alkene accumulation began to increase and
reached a constant limiting value when complex I had
been consumed completely. This limiting rate is equal
the rate of olefin formation from alcohol in acidic
medium in the absence of palladium(II).
logous alkenes toward palladium(II) chloride or
acetate: The reaction rate increases with increasing
hydrocarbon chain length in olefin, in particular, for
olefins with internal double bonds [3 5].
It is known that reactions of linear and branched
olefins with palladium(II) salts yield carbonyl com-
pounds or palladium -allyl complexes [6]. There-
with, several isomers are formed, the highest yield
corresponding to a terminal -allyl complex [reac-
As it was found earlier [1], the rate of formation of tion (1)]:
palladium -allyl complex depends on alcohol con-
centration and does not depend on palladium(II) con-
centration. Thus, we suggested that the limiting stage
of the reaction under study is dehydration of the
parent tertiary alcohol, which is followed by fast re-
action of alkene with complex I. The presence of an
inductive period, during which the rate of olefin
consumption is much greater than the rate of its for-
mation, confirms this mechanism. The obtained data
provide indirect evidence showing that the oxidation
(1)
of tertiary alcohols with tetraaquapalladium(II) ions
occurs via olefin formation.
We earlier isolated and described a palladium
methallyl complex obtained by oxidation of 2-methyl-
2-propanol. Similarly, from the postreaction solution
of complex I and 2-methyl-2-butanol we isolated,
with the help of 2,2 -bipyridyl, a palladium compound
We studied the effect of alcohol structure on the
rate of complex I consumption and found that the
reaction rate increases in the order 2-methyl-2-pro-
panol < 2-methyl-2-butanol < 2-methyl-2-pentanol <
1-methyl-1-cyclohexanol < 1-ethyl-1-cyclohexanol. It
is important to note that the reactivity order of tertiary
alcohols is opposite to the reactivity order of homo-
1
which was characterized by H and 13C NMR spec-
troscopy (Fig. 3).
Based on these and published data [7 10], we came
to a conclusion that the resulting compound is a mix-
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001

REACTIONS OF TERTIARY ALCOHOLS WITH PALLADIUM(II) TETRAAQUA COMPLEX
(a)
1171
5.90 5.80 5.70 5.60
, ppm
4.4
4.2
4.0
3.8
3.6
3.4
, ppm
9.0 8.5 8.0
7.5 7.0 6.5 6.0 5.5 5.0
4.5 4.0 3.5 3.0
2.5 2.0 1.5 1.0
, ppm
(b)
200 190 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20
C, ppm
1
13
Fig. 3. (a) H and (b) C NMR spectra of compounds IIa and IIb.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001

1272
POTEKHIN et al.
Table 1. Effect of alcohol structure on the yield of the
corresponding palladium -allyl complex; Calc 0.1 M,
2-methyl-2-butanol no carbonyl compounds were
found, whereas in the systems with 1-methyl-1-cyclo-
hexanol and 1-ethyl-1-cyclohexanol the yields of
carbonyl compounds were 7 and 14%, respectively,
with respect to consumed palladium(II).
3
CPd(II) 5.5 10 M, and CHClO 0.53 M
4
In the presence of Fe(III)
Yield, %
The yields of target products of olefin oxidation
with palladium(II) are commonly improved by using
various oxidants (co-oxidants) for regeneration of
palladium(II) in the catalytic cycle. In this work we
used as co-oxidants p-benzoquinone, copper(II) and
iron(III) sulfates, and a solution of thallium(III) per-
chlorate.
T,
C
[per
yield, %
[per
consumed
Pd(II)]
Alcohol
consumed CFe(III) ,
Pd(II)]
103, M
2-Methyl-
2-propanol
2-Methyl-
2-butanol
55
45
58
50
at 3 to 25
99
3
5.5
30
13
30
60
120
10
60
120
13
77
87
93
42
39
48
54
1
37
41
28
52
58
79
It is known that p-benzoquinone is the best co-
oxidant for olefin oxidation with palladium(II) in
halide-free [11]. However, in our case p-benzoquinone
and Cu(II) appeared to be inert in the transformations
of alcohols both to -allyl complexes and to oxidation
products. In the presence of Tl(III), complex I was
not consumed for a long time, until Tl(III) had com-
pletely reduced to Tl(I). Later on Tl(I) exerted no
effect on alcohol oxidation with complex I.
2-Methyl-
2-pentanol
40
16
1-Methyl-
1-cyclo-
hexanol
1-Ethyl-
1-cyclo
40
40
1.2
We obtained unexpected results in the oxidation of
alcohols with complex I in the presence of iron(III)
ions. The accumulation of 1-methyl-1-cyclohexene
with time in the presence of complex I and Fe(III) is
shown in Fig. 2, curve 4. As seen from the figure, in
the presence of iron(III) ions the induction period was
much longer, since iron(III) affected the rate of com-
plex I consumption: The lower the rate of complex I
consumption, the longer the period when olefin is not
accumulated in the solution.
30
60
120
hexanola
a
C
0.05 M.
alc
ture
of
two
isomeric
palladium
-allyl
complexes Pd( 3-(CH3)2CCHCH2)bpy]ClO4 (IIa) and
[Pd( 3-(CH2C(CH3)CHCH3))bpy]ClO4 (IIb). The
selectivities with respect to complexes IIa and IIb
were 83 and 17%, respectively. These data suggest
that the dominating direction of the formation of
palladium -allyl complex in the reaction of 2-methyl-
2-butanol with complex I is a pathway in involving
retention of methyl groups at the quaternary carbon
atom. This feature distinguishes the method of syn-
thesis of -allyl complexes, developed in this work
from earlier described methods. We managed to isolate
palladium -allyl complexes from solutions of other
tertiary alcohols. Presently we are studying them by
physicochemical methods. It is likely that the distribu-
tion of possible isomers will be the same.
With aliphatic alcohols, the rate of complex I
consumption varied insignificantly with initial con-
centration of iron(III). With cyclic alcohols, this rate
noticeably decreased with increasing iron(III) con-
centration (Fig. 4). Therewith, the ionic strength I of
1.5 was kept constant by adding NaClO4.
Irrespective of the nature of tertiary alcohol, the
yield of palladium -allyl complexes in the presence
of iron(III) ions essentially increased (Table 1). In all
the systems under study iron(II) formed, implying that
iron(III) ions take part in redox reactions. Addition
of iron(III) ions to the reaction solution resulted in a
considerable reduction in the amount of palladium(0)
(Table 2).
Table 1 lists the yields of palladium -allyl com-
plexes for various alcohols.
The formation of palladium(0) in the reactions of
all the alcohols under study with complex I point to
occurring redox reactions. Taking into account pub-
lished data, we attempted to find carbonyl compounds
in the reaction system using 2,4-dinitrophenylhydra-
zine. In the systems with 2-methyl-2-pentanol and
These data point to a catalytic nature of the oxida-
tion of tertiary alcohols with complex I in the pre-
sence of iron(III), where iron(III) ions appear to func-
tion as the co-oxidant regenerating the oxidized form
of palladium. As seen from Table 2, the ratio of the
total number of Pd(0) moles formed in the reaction
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001

REACTIONS OF TERTIARY ALCOHOLS WITH PALLADIUM(II) TETRAAQUA COMPLEX
1173
without Fe(III) to the change in the number of Fe(III)
moles within the same reaction time in the presence
of Fe(III) ions was not 1/2, as expected for a usual
5
catalysis with iron(III) ions as co-oxidant.
4
Our present data and the kinetic data obtained in
5
[1] allow us to propose the following scheme (with
aliphatic alcohols as example) of the reaction of a
3
4
tertiary alcohol with complex I.
2
[H+]
3
(CH3)2COH(CH2)nCH3
(CH3)2C=CH(CH2)nCH3
[ -Allyl],
1
0
H2O
Pd(II)
k1
1
2
20 40 60 80 100 120 140 160 180 200
Time, min
Pd(II)
[ -Allyl]
Oxidation products + Pd(0).
k2
Fig. 4. Plots of the concentration of complex I vs. time
The tertiary alcohol undergoes a slow acid-cata-
lyzed dehydration reaction to give the corresponding
olefin. The olefin rapidly reacts with complex I to
form a -allyl complex. This organometallic com-
pound is oxidized with complex I to the correspond-
ing products, and Pd(0) is formed. It is important to
note that iron(III) ions do not oxidize the palladium
-allyl complex.
for the oxidation of 1-methyl-1-cyclohexanol at various
3
Fe(III) concentrations. C
5.5 10 M, C 0.1 M,
alc
Pd(II)
and C
0.63 M, 40 C, I 1.5. C
, M: (1) 0,
HClO4
Fe(III)
(2) 0.01, (3) 0.025, (4) 0.06, and (5) 0.12.
for material balance both in the presence and in the
absence of Fe(III) [Eqs. (3) and (4), respectively] for
various k1/k2 ratios allowed us to compare the experi-
mental and calculated kinetic curves.
The rate of accumulation of the palladium -allyl
complex [ -Allyl] can be described by kinetic equa-
tion (2):
C0Pd(II) = [Pd(H2O)]+2 + [ -Allyl],
(3)
aq
C0Pd(II) = [Pd(H2O)]+2 + [ -Allyl] +Pd(0)]. (4)
d[ -allyl]/d = k1[Pd(H2O)4]2+[Ol]
aq
k2[ -allyl][Pd(H2O)4]2+.
(2)
Table 2. Effect of reaction conditions on the amount of
3
the Pd(0) formed; CPd(II) 5.5 10 M, CHClO 0.5 M, and
4
Here [Ol] is olefin concentration.
Calc 0.1 M
Equation (2) is an equation of a self-catalyzed
reaction.
Pd(0), %
T,
C
[Pd(0)]/
Mathematical analysis of the kinetic equation
allows the following assumptions. When the rate
constant k1 considerably exceeds the rate constant k2,
the yield of the palladium -allyl complex will
increase and palladium(0) will be formed in minor
amounts. Such a situation seems to take place with
aliphatic alcohols, particularly in the oxidation of
2-methyl-2-propanol and 2-methyl-2-butanol. When
the rate constants are equal to each other or when k2 is
higher than k1, the amount of the palladium(0) formed
will increase, and the yield of the -allyl complex will
decrease, as is observed with tertiary cyclic alcohols.
Iron(III) additives prevent accumulation of palla-
dium(0). As a result, the rate of formation and the
yield of the -allyl complex increase and, on the other
hand, its decomposition rate decreases.
Alcohol
without
Fe(III)
with
[Fe(III)]b
Fe(III)a
2-Methyl-2-
propanol
2-Methyl-2-butanol 45
55
40
0c
1/0.5
51
56
5
1/1
1/1
2-Methyl-2-
pentanol
1-Methyl-1-cyclo-
hexanol
40
40
40
25
87
96
7
7
1/1.5
1/1.5
1-Ethyl-1-cyclo-
hexanold
a
b
At the Fe(III) concentration 0.12 M.
Ratio of the total
number of Pd(0) moles ( ) formed in the reaction without
Fe(III) to the change in the number of Fe(III) moles within the
same reaction time in the presence of Fe(III) ions. At Fe(III)
c
Solution of differential equations for 2-methyl-2-
propanol and 1-methyl-1-cyclohexanol with account
3
d
concentrations of 3 10 M and higher.
C
0.05 M.
alc
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001

1174
POTEKHIN et al.
6
(a)
(a)
5
4
5
4
1
2
3
2
1
2
3
2
1
0
1
0
10
20 30
(b)
40 50 60
6
(b)
5
5
4
3
2
1
4
3
0
50
100
150
200
Time, min
0
50
100
150
200
Time, min
Fig. 5. Plots of the concentration of complex I vs. time
(a) for the reaction with 2-methyl-2-propanol and (b) for
the same reaction in the presence of Fe(III). (1) Calcula-
tion and (2) experiment.
Fig. 6. Plots of the concentration of complex I vs. time
(a) for the reaction with 1-methyl-1-cyclohexanol and
(b) for the same reaction in the presence of Fe(III).
(1) Calculation and (2) experiment.
In all the cases the calculated curves fairly fitted
experimental (Figs. 5 and 6) at a k1/k2 ratio of 40 for
2-methyl-2-propanol and of 2.5 for 1-methyl-1-
cyclohexanol.
using the absorption band of a palladium tin complex
(
635 nm) [14]. The concentration of palladium
bomuanxd in -allyl complex was determined by the dif-
ference in the palladium(II) concentrations in a sample
with added aqua regia and without it. Before analysis
palladium(0) was removed from solutions by centri-
fugation. The concentration of iron(III) in the course
of reaction was determined by spectrophotometry
using the color reaction with 10% 2-hydroxy-5-sulfo-
EXPERIMENTAL
The NMR spectra were obtained on a Bruker PDX-
300 instrument in (CD3)2CO.
benzoic acid (
510 nm) [15]. The optical densities
were measuredmaoxn an FEK-56M photoelectrocolori-
meter.
All reactions were carried out in a temperature-
controlled bubbling reactor equipped with a sampler.
Complex I was prepared by the procedure in [12].
Chemical grade 2-methyl-2-propanol and 2-methyl-2-
The progress of olefin formation was controlled as
pentanol were used. 2-Methyl-2-butanol, 1-methyl-1- follows. Argon was continuously passed through the
cyclohexanol, and 1-ethyl-1-cyclohexanol were pre-
pared by the procedure in [13]. The concentration of
perchloric acid in the initial solution of complex I was
determined by acid base titration. The concentration
of complex I was determined by spectrophotometry
reaction solution and then directed through a glass
outlet tube to an ice-cooled methanol trap. The traps
were changed at intervals dictated by the kinetics.
Quantitative analysis for alkenes was performed by
iodometric titration [16], and their structures were
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001

REACTIONS OF TERTIARY ALCOHOLS WITH PALLADIUM(II) TETRAAQUA COMPLEX
1175
determined by NMR spectroscopy after replacement
of the methanol in the traps by deuterochloroform.
4. Rylander, P.N., Organic Synthesis with Noble Metal
Catalysts, New York: Academic, 1973.
5. Dird, C.W., Transition Metal Intermediates in Or-
ganic Synthesis, London: Logos, 1967.
The concentrations of alcohols were determined by
GLC on a Tsvet-100 chromatograph (flame-ionization
detector, 1000 3-mm metallic column, liquid phase
Apiezon-L). The oven temperature was 100 140 C
(depending on alcohol structure), carrier gas nitrogen
(34 ml/min), internal standard isopropanol.
6. Huttel, R. and Christ, H., Chem. Ber., 1964, vol. 97,
no. 5, pp. 1439 1452.
7. Huttel, R. and McNiff, M., Chem. Ber., 1964,
vol. 106, no. 7, pp. 1789 1803.
8. Potekhin, V.V., Skvortsov, N.K., Antonov, N.G.,
Bel’skii, V.K., and Ukraintsev, V.B., Zh. Obshch.
Khim., 1997, vol. 67, no. 8, pp. 1233 1236.
Palladium -allyl complexes were isolated by
adding excess 2,2 -bipyridyl to the reaction solutions
after reaction completion. The resulting white preci-
pitate was filtered off and washed with water and
ether.
9. Canovese, L., Visentin, F., Vquagliati, P., Chessa, G.,
and Pesce, A., J. Organomet. Chem., 1998, vol. 566,
no. 1, pp. 61 71.
1
Complex Ia. H NMR spectrum, , ppm: 1.46 s
10. Albinati, A., Ammann, C., and Pregosin, P.S., Organo-
metallics, 1990, vol. 9, pp. 1826 1833.
(3H, anti-CH3) 1.84 s (3H, syn-CH3), 3.94 d (1H, syn-
3
3
H3, J 13.3 Hz), 4.38 d (1H, syn-H3, J 8.2 Hz),
5.74 d.d (1H, H2, 3JHH-anti 13.3, 3JHH-syn 8.2 Hz).
11. Matveev, K.I., Kinet. Katal., 1977, vol. 18, no. 4,
pp. 862 877.
1
Complex IIb. H NMR spectrum, , ppm: 1.68 d
3
12. Ioffe, S.T. and Nesmeyanov, A.N., Metody element-
organicheskoi khimii (magnii, kal’tsii, berilii, strontsii,
barii) [Methods of Organometallic Chemistry
(Magnesium, Calcium, Beryllium, Strontium, Barium)],
Moscow: Akad. Nauk SSSR, 1963.
(3H, CH3, J 7.2 Hz), 2.25 s (3H, CH3), 3.46 s (1H,
3
anti-H1), 4.27 s (1H, syn-H1), 4.16 q (1H, H3, J
7.2 Hz).
ACKNOWLEDGMENTS
13. Shitova, N.B., Matveev, K.I., and Kuznetsova, L.I.,
Izv. Sib. Otd. Akad. Nauk SSSR, Ser. Khim., 1973,
no. 2, issue 1, pp. 25 30.
The authors are grateful to M. Yu. Starodubtsev
for the help in preparing tertiary alcohols and to
N.G. Antonov for taking NMR spectra.
14. Ginzburg, S.I., Analiticheskaya khimiya platinovykh
metallov (Analytical Chemistry of Platinum Metals),
Moscow: Nauka, 1972.
REFERENCES
15. Marczenko, Z., Kolorymetryczne oznaczanie pierwias-
tow (Photometric Determination of Elements),
Warsaw: Wyd. Naukowo-Techniczne, 1968.
1. Ryadinskaya, N.Yu., Potekhin, V.V., Skvortsov, N.K.,
and Potekhin, V.M., Zh. Obshch. Khim., 2000, vol. 70,
no. 7, pp. 1153 1157.
16. GOST 2070 82. Metody opredeleniya iodnykh chisel i
soderzhaniya nepredel’nykh uglevodorodov (State
Standard 2070 82. Methods of Determination of
Iodine Numbers and Contents of Unsaturated Hydro-
carbons).
2. Robinson, S.D. and Shaw, B.L., J. Chem. Soc., 1963,
no. 10, pp. 4806 4814.
3. Parshall, G.W., Homogeneous Catalysis, New York:
Interscience, 1980.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 71 No. 8 2001