1024
A. M. EGOROV, S. A. MATYUKHOVA AND A. V. ANISIMOV
Organic reaction products were analyzed on a Hewlett-
Synthesis of gaseous DCl was carried out by interac-
tion of sulfuric acid-d2 (Aldrich Chemical, 98%) with
NaCl in the presence of DCl (37% solution in D2O;
Aldrich Chemical).
Packard GC–MS instrument (HP 5972 mass-selective
detector and HP 5890 gas chromatograph) using a capil-
lary column (30 m ꢁ 0.25 mm i.d.) with a diphenyl (5%)
stationary phase supported on polydimethylsiloxane.
The column temperature was 40–250 ꢂC; the heating
rate was 30 ꢂC minꢃ1. Helium was used as the carrier
gas (at a flow-rate of 1 ml minꢃ1). The injector tempera-
ture was 250 ꢂC and the detector temperature was 280 ꢂC.
Specific polarized light plane rotation was measured on
an A-1 EPO automatic polarimeter (ꢂ ¼ 0.01ꢂ).
3-Methylpyridine (Janssen) was dried with fused KOH
and distilled twice over KOH in an inert gas atmosphere;
b.p. 143.7–144 ꢂC; nD ¼ 1.5067 (lit.12 b.p. 144.0 ꢂC;
20
20
nD ¼ 1.5068).
All solvents were purified according to standard pro-
cedures.13 They were freed from dissolved gases by
repeatedly freezing and thawing at reduced pressure
and stored in ampoules in the absence of air.
Inorganic reaction products [Cu(I) and Cu(II) cations]
were determined by ion chromatography on a Tsvet-
3006 chromatograph by using Diacat-3 columns (150 ꢁ
3 mm i.d.) (Elsiko, Moscow, Russia). An aqueous 4 mM
ethylenediamine, 5 mM citric acid and 5 mM tartaric
acid solution was used as the eluent at a flow-rate of
15 ml minꢃ1. The sample volume was 100 ml (after
1:1000 dilution with water).
Reaction of benzyl chloride with copper;
general procedure
A 1 g portion of Cu powder was dissolved in 10 ml of
DMF and 5 ml of benzyl chloride in an argon atmosphere
at 70 ꢂC. After 5 h, the white precipitate formed (which
rapidly became green in air) was filtered off in an atmo-
sphere of oxygen-free argon. Recrystallization from
3-MePy yielded 4.90 g (83%) of yellow crystals of tris-
3-methylpyridine copper(I) chloride [Cu(3-MePy)3Cl],
which were stable in air.14 Analysis: C18H21N3CuCl
calculated, Cu 16.49, Cl 9.37, C 57.14, H 5.59, N
11.10; found, Cu 16.50, Cl 9.32, C 56.88, H 5.68, N
11.06%. IR (mineral oil), ꢄ ¼ 475 (m, Cu–N), 420 (w,
Cu–N), 350 (s, Cu–N), 320 (s, Cu–Cl), 292 (s, Cu–Cl),
Reagents
Copper powder of >99.99% purity was prepared by the
reduction of CuSO4 (analytical grade) with magnesium
powder (MP-1, Khlorvinil, Ukraine) in oxygen-free argon.
A copper wire covered with a varnish film (GOST
7262-54, Russia; Cu content 99.99%) 0.2 mm in diameter
was held in DMF for 24 h. Just before the experiment, the
sample was mechanically purified to remove the swollen
insulating film, exposed to concentrated nitric acid for
5–10 s and washed with water, acetone and DMF. The
entire operation was carried out in oxygen-free argon.
All organic compounds were obtained commercially.
The purity of commercial samples (Aldrich Chemical) of
benzyl chloride, 3-methylbenzyl chloride, 4-methylben-
zyl chloride, 3-methoxybenzyl chloride, 4-fluorobenzyl
chloride, 3-fluorobenzyl chloride, 3-chlorobenzyl chlor-
ide, 4-methoxybenzyl chloride and 4-chlorobenzyl
chloride was checked by GC. Compounds which con-
tained toluene or were <99% pure were purified by low-
temperature fractional recrystallization or by fractional
distillation in the case of liquids or by recrystallization
from ethanol in the case of solids.
230 (vs Cu–N) cmꢃ1
.
Organic products of reaction were extracted with
diethyl ether (20 ml). The residues of benzyl chloride
and DMF, and also 1,2-diphenylethane and 4,40-di-
methylbiphenyl, were detected in the ether solution.
The isolated yield of 1,2-diphenylethane was 1.37 g
1
(96%); m.p. 51–52 ꢂC (lit.15 m.p. 51–52 ꢂC). H NMR
(CDCl3): ꢂ ¼ 2.82 (s, 4H, CH2), 7.02 (m, 10H, Ph.) ppm.
MS (EI, 70 eV): calculated m/z 182.11 (M); found 182
[M]þ (23), 91 [M/2]þ (100).
4,40-Dimethylbiphenyl, MS (EI, 70 eV): calculated m/z
182.11 (M), found 182 [M]þ (100), 167 [MꢃCH3]þ (56),
152 [Mꢃ2CH3]þ (15).
Study of the reaction kinetics
Synthesis of ( þ )-(R)-1-chloro-1-phenylethane was
carried out by interaction of (ꢃ)-(S)-1-phenylethanol
with POCl3 in the presence of pyridine in pentane. Yield
The reactions of copper with nine benzyl chlorides in
DMF were studied by the resistometric method16 accord-
ing to the published procedure17 in an atmosphere of
water-free argon freed from oxygen. The reaction ki-
netics were studied by monitoring the electrical resis-
tance of species during experiments. Species were copper
wire (diameter 0.2 mm and length 100 mm). Conse-
quently, an increase in electrical resistance reflects a
decrease in the thickness of the wire.
25
76%; b.p. 80–81 ꢂC/17 mmHg, [ꢃ]D þ94.1ꢂ (l ¼ 1). Lit.
25
data: b.p. 78–82 ꢂC/17 mmHg, [ꢃ]D þ125.4ꢂ (l ¼ 1,
100%).9 1H NMR (CDCl3): ꢂ1.68 (d, 3H, CH3), 4.86
(dd, 1H, CH), 7.14 (m, 5H, Ph).
Synthesis of (ꢃ)-(S)-1-phenylethanol was carried out as
described in the literature.10,11 Yield 55%; b.p. 94–95 ꢂC/
25
14 mmHg, [ꢃ]D ꢃ37.65ꢂ (l ¼ 1). Lit. data: b.p. 94–
95 ꢂC/14 mmHg, [ꢃ]D ꢃ44.2ꢂ (l ¼ 1).11 1H NMR
25
To obtain kinetic and thermodynamic parameters of the
process, three series of experiments were carried out. The
first was carried out at initial CRCl ¼ 0.5 mol lꢃ1 with
(CDCl3): ꢂ 1.21 (d, 3H, CH3), 3.78 (q, 1H, CH), 7.06
(m, 5H, Ph).
Copyright # 2005 John Wiley & Sons, Ltd.
J. Phys. Org. Chem. 2005; 18: 1023–1031