Reactions of phenylethynyl cuprates of lanthanides with organyl halides and synthesis of the related polyfunctional compounds

Article abstract of DOI:10.1134/S1070363214110206

Phenylethynyl cuprate complexes of lanthanides react with organyl halides RX, Ph₃CX, R₃SiX, and RC(O)X (X = Cl, I; R = alkyl) in tetrahydrofuran to give polyfunctional organic and hetero-organic compounds with high yield. The reactio

Full text of DOI:10.1134/S1070363214110206

ISSN 1070-3632, Russian Journal of General Chemistry, 2014, Vol. 84, No. 11, pp. 2167–2173. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © S.F. Zhil’tsov, O.N. Druzhkova, M.A. Dydykina, V.M. Makarov, 2014, published in Zhurnal Obshchei Khimii, 2014, Vol. 84, No. 11,
pp. 1870–1877.
Reactions of Phenylethynyl Cuprates of Lanthanides
with Organyl Halides and Synthesis
of the Related Polyfunctional Compounds
S. F. Zhil’tsov, O. N. Druzhkova, M. A. Dydykina, and V. M. Makarov
Minin Nizhni Novgorod State Pedagogical University, ul. Ul’anova 1, Nizhni Novgorod, 603950 Russia
e-mail: chemical@mininuniver.ru
Received June 16, 2014
Abstract—Phenylethynyl cuprate complexes of lanthanides react with organyl halides RX, Ph3CX, R3SiX, and
RC(O)X (X = Cl, I; R = alkyl) in tetrahydrofuran to give polyfunctional organic and hetero-organic compounds
with high yield. The reaction mechanism is discussed.
Keywords: phenylethynyl cuprates of ytterbium(II) and praseodymium(III), organyl halide, reaction mechanism,
synthesis, polyfunctional compounds
DOI: 10.1134/S1070363214110206
Procedures to prepare phenylethynyl cuprates
of lanthanides were developed earlier [1, 2]. In
particular, homoleptic phenylethynyl compounds
of ytterbium(II), europium(II), praseodymium(III),
and erbium(III) reacted with phenylethynylcopper
at room temperature in tetrahydrofuran (THF) to
yield the corresponding cuprates with high yields
(80–97%).
THF, 20oC
{[(PhC
2(PhC
C)2Yb + 2PhC CCu
C)3Cu][Yb(THF)2]}2,
(1)
I
THF, 20oC
[(PhC
2(PhC
C)3Cu]3[Pr2(THF)6].
C)3Pr + 3PhC CCu
(2)
II
The cuprate complexes are fairly sensitive to
oxygen and moisture. Their hydrolysis with excess of
water in THF at room temperature gave phenyl-
ethynylcopper, phenylacetylene, and the lanthanide
hydroxide with almost quantitative yields.
furan)ytterbium tris(phenylethynyl)cuprate (I) was a
dimer (see figure).
Solution of complex I in THF behaved as weak
electrolyte, as evidenced by measured conductivity
(λ∞ 1.2 cm2 Ω–1 mol–1, 20°С) and the dissociation
constant (Kg 2.62 × 10–7). Dissociation of complex I
occurred according to Eq. (3).
X-ray diffraction analysis showed that bis(tetrahydro-
THF
THF
C)3Cu]2b_
C_
2[Yb(ТHF)2]2+ + 4PhC
+ 2PhC CCu
2[Yb(THF)2]2+ + 2[(PhC
I
a
THF
_
2(PhC
C)2Yb(ТHF)2 + 2PhC
CCu.
(3)
c
The reaction equilibrium was shifted towards
formation of phenylethynylcopper insoluble in THF in
the course of the ate-complex hydrolysis. Taking into
account the ability of the parent cuprates to undergo
dissociation [Eq. (3)], it was reasonable to suggest that
reactions (1) and (2) were reversible; that was a factor
2167

2168
ZHIL’TSOV et al.
triphenylmethyl chloride, trimethylsilicon iodide, and
acetyl chloride) and revealed their applications to
prepare polyfunctional compounds, combining various
hydrocarbon fragments as well as various functional
groups in the structure. Interaction of the halides with
phenylethynyl cuprate of a lanthanide in THF was
accompanied by change of the solution color and
precipitation of phenylethynylcopper and the
lanthanide halide.
The cuprate I reacted with methyl iodide (at the 20-
fold excess of the latter) in THF at room temperature
to form phenylethynylcopper, methylphenylacetylene,
and ytterbium iodide (in the form of complex with
THF) with high yields [Eq. (4)].
THF
I + CH3I
CCH + YbI (THF) .
PhC≡
CCu + PhC≡
74%
3
2
4
(4)
86%
96%
Molecular structure of the {[(PhC≡C)3Cu][Yb(THF)2]}2 (I)
complex.
The almost quantitative yield of phenylethynyl-
copper pointed at its indifference towards methyl iodide.
Reaction (5) of the cuprate complex I with benzyl
chloride (the molar ratio of 1 : 4 was taken according
to the number of phenylethynyl groups capable of the
substitution) occurred in THF at 50°С. After incuba-
tion of the reaction mixture at 90°С during 4 h, benzyl-
phenylacetylene was isolated with yield of 83%.
explaining the instability of cuprate complexes I and II
in the presence of oxygen and moisture.
In this work we studied reactions of phenylethynyl
cuprates of praseodymium and ytterbium with various
organyl halides (methyl iodide, benzyl chloride,
THF
(5)
2PhC
87%
I + 4C6H5CH2Cl
CCu + 4C6H5CH2C
CPh + 2YbCl2(THF)4.
84%
83%
Taking into account the ability of the parent cuprate
complex towards ionization in THF and the high yield
of cross-coupling products PhC≡CR (R = CH3,
C6H5CH2) in reactions (4) and (5), we concluded that
the phenylethynyl carbanions formed as intermediates
[Eq. (3), part b] could interact with the halide RX via
nucleophilic substitution [Eq. (6)].
The cross-coupling product triphenylmethylacetylene
was not formed. ESR could detect the presence of
triphenylmethyl radicals revealing the hyperfine
interaction constant with protons of аНo 0.255, аНm
0.111, and аНp 0.278 mT; g 2.0027. Formation of phenyl-
acetylene was observed, further polymerizing into
polyphenylacetylene.
δ+
PhC C + R
δ−
The interaction of dimeric cuprate I with tri-
phenylmethyl chloride at a molat ratio of 1 : 4 in THF
at room temperature was accompanied by formation of
phenylethynylcopper (91%), tetrahydrofuranates of
phenylethynylytterbium chloride (71%), ytterbium
chloride (18%), 1-(diphenylmethyliden)-4-(triphenyl-
methyl)-2,5-cyclohexadiene (63%), phenylacetylene
and polyphenylacetylene (67%). Besides phenyl-
ethynylcopper, the products common with the similar
reaction of bis(phenylethynyl)ytterbium with triphenyl-
methyl chloride [3] were formed. That suggested that
the cuprate I acted as carrier of bis(phenylethynyl)-
(6)
X
PhC CR + X
.
The halogenide ions Х– further recombined
Eq. (7) with ytterbium cations formed according to
Eq. (3).
THF
Yb(THF)22+ + 2X
YbX2(THF)4,
(7)
X = I, Cl.
Reaction of the ytterbium cuprate complex I with
triphenylmethyl chloride occurred in a different way.
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REACTIONS OF PHENYLETHYNYL CUPRATES OF LANTHANIDES
2169
ytterbium [Eq. (3), part c] that reacted with triphenyl-
methyl chloride via the radical-heterolytic mechanism
to undergo stepwise dealkynylation including the stage
of one-electron transfer [Eq. (8)].
THF
(PhC
PhC
C)2Yb + Ph3CCl
CYb :C
Cl CPh3
CPh
4
Ph3CCl
THF
(8)
Ph3C + PhC
YbCl2(THF)4 + PhC
C
+ PhC
C + Ph3C .
CYbCl(THF)2
Additionally, triphenylmethyl chloride could
directly interact with phenylethynyl ions formed at the
Eq. (3), b stage. However, taking into account that
positive charge at methyl atom of triphenylmethyl
chloride was more delocalized than that in benzyl
chloride, that interaction did not lead to cross-
coupling; instead, the process involving a one-electron
transfer was more probable [Eq. (9)].
and 6 : 1, respectively, in THF at room temperature led
to separation of phenylethynylcopper [see reaction (3)].
Other products were similar to those of the reactions of
phenylethynyl lanthanides (PhC≡C)nLn (Ln = Yb, Pr;
n = 2, 3) with trimethylsilicon halogenide [6, 7]; those
reactions were accompanied by formation of
trimethylsilicon phenylacetylenide with yield of 91–
95% (with respect to the substituted PhC≡C groups in
the starting cuprate). The presence of phenylacetylene
(5–10%) in the reaction mixtures was observed as
well, being likely due to generation of phenylethynyl
radicals as a result of the side process similar to the
reactions (8) and (9).
_e
δ+
CPh3
(9)
PhC C: + Cl
PhC≡C + Ph3C + Cl−.
Interaction of the counter-ions (chloride ions) and
the ions generated via reaction (3), part b stipulated for
formation of lanthanide compounds in the reaction.
Triphenylmethyl radicals recombined to form equi-
librium mixture with 1-(diphenylmethyliden)-4-(tri-
phenylmethyl)-2,5-cyclohexadiene [Eq. (10)].
Reactions of cuprate complexes of lanthanides with
hetero-organic halides could serve as model process
for production of asymmetric polyfunctional hetero-
organic compounds.
Phenylethynyl cuprates of ytterbium and praseo-
dymium reacted with acetyl and benzyl chlorides in
THF at room temperature. In contrast to lithium
organic cuprates [R2Cu]Li forming ketones in high
yield when reacting with acyl halides [8], the
interaction of lanthanides cuprate complexes with
acetyl chloride resulted in formation of polyfunctional
alkoxy derivatives of ytterbium and praseodymium,
being the products of addition of the (PhC≡C)nLn
(Ln = Yb, Pr; n = 2, 3 respectively) intermediates at
carbonyl group of acetyl halide [9]. Further studies
revealed the process mechanism in detail.
CPh3
(10)
2Ph3C
Ph2C
H
Phenylethynyl radicals could detahydrogen atoms
from THF to form phenylacetylene; the latter was
detected mainly in the form of polyphenylacetylene by
IR spectroscopy [4].
Hetero-organic derivatives could be used as organyl
halides as well [5]. In particular, interaction of
trimethylsilicon iodide with phenylethynyl cuprates of
ytterbium and praseodymium at the molar ratio of 4 : 1
CH3
Cl
O
PhC C + CH3C
CH3
PhC C C O
Cl
Cl
CH3
Cl
(11)
+ [Yb(THF)2]2+
(PhC C C O)2Yb(THF)2.
2
PhC C C O
Reaction of the cuprate complex I with acetyl chloride
at the molar ratio of 1 : 4 yielded phenylethynylcopper
(96%) and the paramagnetic alkoxy derivative of
ytterbium(III) (92%) having effective magnetic
moment of 4 µB; according to the reference data that
value was typical of Yb(III) compounds. Synthesis of
the latter product is represented by scheme (11).
Phenylethynyl carbanions formed in reaction (3) were
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2170
ZHIL’TSOV et al.
added to acetyl chloride, and the so formed alkoxide
ions reacted with ytterbium counter-ions.
being almost the same as in the previous case. Hence,
we suggested that one of the chlorine atoms moved
from the inner sphere of the complex into the outer
sphere, according to the synchronous process (12).
Formation of the alkoxide was accompanied with
its oxidation into the Yb(III) derivative, its molar mass
_e
Cl
CH3
CH3
Cl
Cl
CH3
CH3
THF
PhC C C O Yb O C C CPh Cl
(THF)2
PhC C C O Yb O C C CPh
(THF)2
O
H
Cl
CH3
CH3
CH3
Cl
CH3
H
Cl
PhC C C O Yb O C C CPh.
(12)
PhC C C O Yb O C C CPh Cl
(THF)2
(THF)2
III
The substituent in the lanthanide alkoxide was at
chloromethyloxy]ytterbium chloride was identified
in the form of its bistetrahydrofuranate by ele-
mental analysis and IR spectroscopy data as
well as by products of its hydrolysis in THF
[Eq. (13)].
the same time
a
redox-active ligand capable
of oxidation as well as of reduction. The isolated
asymmetric ytterbium alkoxychloride III, [methyl-
(phenylethynyl)methyloxy][methyl(phenylethynyl)-
THF
(13)
III + H2O
PhC CCH(OH)CH3 + PhC CC(O)CH3 + Yb(OH)Cl2.
Methyl(phenylethynyl)carbinol and methyl(phenyl-
ethynyl)ketone were detected by IR spectroscopy using
the characteristic absorption of О–Н (3435 cm–1,
associated, broad band), С=О (1738 cm–1), and C≡CPh
(2204 cm–1). Total yield of the products was of 1.8 mol
per 1 mol of the starting complex III.
To investigate the ability of the formed complex III to
react with acetyl halide, the reaction was run in the
excess of the latter using hexa(tetrahydrofuranate)-
dipraseodymium tris(priphenylethynyl cuprate) II. Its
interaction with acetyl chloride resulted in symmetric
praseodymium alkoxide IV. At the molar ratio of the
reactants of 1 : 8 the formed alkoxide reacted with
excess of acetyl chloride to yield a polyfunctional
ester, 1-(phenylethynyl)-1-chloroethyl ethanoate V,
and bis[methyl(phenylethynyl)chloromethyloxy]praseo-
dymium chloride tetrahydrofuranate VI with yields of
0.7 and 0.8 mol, respectively, per 1 mol of the alkoxide
IV [Eq. (14)].
Samarium alkoxides react with acyl halides to form
esters [10]. The corresponding ester was not observed
among the products of reaction of phenylethynyl
ytterbium cuprate with acetyl chloride at the molar
ratio of 1 : 4. The initial acetyl chloride was
exclusively consumed for the complex III formation.
O
THF
(14)
[PhC CCCl(CH3)O]3Pr + CH3C
PhC CCCl(CH3)OCOCH3 + [PhC CCCl(CH3)O]2PrCl THF.
VI
Cl
IV
V
The ester V was identified by IR and NMR
spectroscopy and elemental analysis, and structure of
the alkoxide VI was confirmed by elemental analysis
and by product of its hydrolysis [methyl(phenyl-
ethynyl)ketone PhC≡CC(O)CH3], the composition and
structure of the latter being in turn elucidated by
elemental analysis and IR and NMR spectroscopy.
At the molar ratio of II to acetyl chloride of 1 : 12
the reaction gave phenylethynylcopper, praseodymium
trichloride, and the ester V, yield of the latter being up
to 1.85 mol per 1 mol of the starting complex II. A
solid visually homogeneous substance soluble in THF
and insoluble in hexane was isolated from the reaction
mixture. Its IR spectrum contained the absorption
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REACTIONS OF PHENYLETHYNYL CUPRATES OF LANTHANIDES
2171
Yield of polyfunctional reaction products
bands characteristic of the ester V and the coordinated
THF. Seemingly, praseodymium chloride and
phenylethynylcopper formed the complex VII, similar
to the cuprate II [Eq. (15)]. Unfortunately, complex
VII could not be isolated in the crystalline state.
Compound
C6H5CH2C≡CC6H5
84
71
70
65
80
3PhC≡CCu + 2PrCl3
C6H5C≡C(CH3)CClOCOCH3
C6H5C≡CC(O)CH3
THF, V
.
[(PhC≡C)Cl2Cu]3Pr2 4THF.0.5PhC≡CCCl(CH3)OCOCH3.
(CH3)3SiC≡CC6H5 [bp 82°С (6 mmHg)]
(15)
VII
[C6H5C≡C(CH3)CClO]2PrCl(THF)
(decomp. 205–207°С)
Incubation of a mixture of complex VII in THF and
water during 2 h at 50°С resulted in formation of the
ester V and its partial hydrolysis into methyl(phenyl-
ethynyl)ketone.
92
C6H5C≡C−CH(CH3)−O−Yb−O−CCl(CH3)−C≡CC6H5
Cl
(THF)2
(decomp. 140°С)
Hence, reaction of phenylethynyl cuprates of ytter-
bium(II) and praseodymium(III) with acetyl chloride in
THF could yield novel lanthanide alkoxides and ester
V, depending on the reagents ratio.
Reactions of complexes I and II with trimethyl-
silicon iodide were described elsewhere [5].
Reaction of complex I with methyl iodide. 2.1 g
(14.8 mmol) of CH3I was added to a solution of 1 g
(0.73 mmol) of the ate-complex I in 20 mL of THF.
The reaction mixture was stirred at room temperature
during 3 h. Formation of yellow precipitate of
PhC≡CCu (mp 220°С) was observed, yield 0.23 g
(1.4 mmol, 96%). After the precipitate separation off,
the filtrate was condensed under vacuum into a liquid
nitrogen-cooled trap. Hexane was added to the non-
volatile residue, YbI2(THF)4 precipitated. Yield 0.9 g
(1.26 mmol, 86.3%). Found, %: Yb 24.45; I 35.44.
C16H32I2O4Yb. Calculated, %: Yb 24.19; I 35.52.
To conclude, we demonstrated that reactions of
phenylethynyl cuprates of lanthanides with organyl
halides could be used as potential procedures to
prepare polyfunctional organic and hetero-organic
compounds with high yields (see table).
EXPERIMENTAL
IR spectra were recorded using a FSM 1201 IR-
Fourier spectrometer. The analyzed samples of the
compounds instable in air were prepared under
vacuum or under argon, the form of Vaseline oil
suspension. Chromatographic analysis of the volatile
Methylphenylacetylene (about 70%) was detected
in the hexane filtrate by GLC.
compounds was performed using
a
Tsvet-100
chromatograph equipped with a katharometer detector
(columns: 100 × 0.3 cm and 200 × 0.3 cm; filled with
PEG-1500, 20% on Khezasorb AW-HMDS; carrier
gas: helium). ESR spectrum of triphenylmethyl radical
was recorded using a Bruker ER 2000-SRC instrument.
Reaction of complex I with benzyl chloride.
0.44 g (3.47 mmol) of benzyl chloride was added to a
solution of 1.2 g (0.87 mmol) of I in 20 mL of THF.
The reaction was monitored by the change of the
reaction mixture color. At room temperature no visual
changes occurred within 16 h. Upon heating to 50°С,
the red solid complex I was dissolved within 2 h, and
the solution turned green-yellow. The reaction mixture
was incubated at 90°С during 4 h. The formed
precipitate, a mixture of phenylethynylcopper and
ytterbium chloride tetrahydrofuranate YbCl2(THF)4,
was separated off, washed with THF, and dried. Yield
0.76 g. Part of the precipitate was mineralized, and
further content of Cu2+, Yb3+, and Cl⎯ was quantified.
Preparation, purification, and isolation of all the
compounds instable in air were carried out in the
evacuated sealed ampoules using the Schlenk
technique. Organic solvents were purified as described
elsewhere [11]. THF and hexane were distilled from
sodium–benzophenone solution, degassed, and put into
an evacuated ampoule with sodium “mirror.” The
required amount of the solvent was sampled via
vacuum condensation.
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ZHIL’TSOV et al.
Another part of the precipitate was treated with hot
of 3.08 g (1.7 mmol) of compound II in 15 mL of
THF; the II : CH3CОCl molar ratio was of 1 : 8. The
reagents mixing was accompanied by heating of the
reaction mixture and precipitation of yellow
phenylethynylcopper mixed with alkoxide VI. To
ensure the complete reaction, the mixture was in-
cubated at room temperature during 5 d. The pre-
cipitate insoluble in THF (1.1 g) was separated off,
washed with THF, dried, and treated with nitric acid in
the presence of H2O2. Concentrations of the formed
Cu2+ ions (yield 0.32 g, 99%), Pr3+, and Cl¯ (the molar
ratio of 1 : 3) were found by titration. Pr mass 0.05 g,
~10% with respect to the initial compound II.
benzene to separate phenylethynylcopper from ytter-
bium chloride. Cooling of the benzene solution gave
yellow precipitate of phenylethynylcopper. Yield 0.25 g
(1.52 mmol, 87.3%), mp 220°С. Found Cu, %: 38.98.
C8H5Cu. Calculated Cu, %: 38.60.
THF was distilled off the filtrate, and hexane was
added to the non-volatile residue to precipitate ytter-
bium chloride. The precipitate was separated off,
washed with hexane, evaporated, and dried under
vacuum. Yield 0.28 g YbCl2(THF)4. Total yield 0.78 g
(1.46 mmol, 84%). Found, %: Yb 32.86; Cl 13.57.
C16H32Cl2O4Yb. Calculated, %: Yb 32.52; Cl 13.34.
The volatile reaction products were re-condensed
from THF mother liquor into a trap cooled with liquid
nitrogen. The distillate did not contain phenylacetylene
and acetyl chloride. Hexane was added to the oily
residue. The precipitated alkoxide VI was separated
off, washed with hexane, and dried to constant mass of
1.67 g (2.7 mmol, yield ~80%). Brown solid, mp 205–
207°С (decomp.). IR spectrum (Vaseline oil), ν, cm–1:
3050, 2900–3000 s, 1677, 1598, 1489, 1251, 1029,
756, 697. Found, %: С 46.84; Н 3.25; Cl 15.33; Pr
24.56. C24H24Cl3O3Pr. Calculated, %: C 47.41; H 3.95;
Cl 17.53; Pr 23.21.
Slow evaporation of the hexane filtrate at ~5°С
gave light-yellow crystals of 1,3-diphenylpropyne,
molten at room temperature. Yield 0.56 g (83.9%).
Found, %: С 92.39; H 6.29. C15H12. Calculated, %: C
93.75; H 6.25.
Reaction of complex I with triphenylmethyl
chloride. 1.11 g (4.0 mmol) of triphenylmethyl
chloride was added to a solution of 1.37 g (1.0 mmol)
of complex I in 20 mL of THF. The reaction mixture
was stirred at room temperature during 3 d. The
precipitate was formed, containing phenylethynyl-
copper (0.3 g, 1.82 mmol, 91%) and ytterbium chloride
YbCl2(THF)4 (0.2 g, 0.37 mmol, yield 18.5%). Phenyl-
ethynylcopper was recrystallized from benzene (mp
220°С). THF and the volatile reaction products were
distilled off the filtrate. Phenylacetylene was detected
in the distillate (yield ~7%, GLC).
Removal of the solvent from the hexane extract
gave 0.54 g (71 mol%) of methyl(phenylethynyl)-
chloromethyl ethanoate V. IR spectrum (Vaseline oil),
ν, cm–1: 1734 s, 3458 w (С=О), 1238 s (С–О), 1030 s
1
(С–О–С), 2204 m (С≡С). Н NMR spectrum (400
MHz, CDCl3), δ, ppm: 7.58–7.38 m (2Н), 7.24–7.05
d.d (1H, 76 Hz), 2.06 s (3H), 1.83 s (3H). Found, %: С
65.24; Н 5.81. C12H11ClO2. Calculated, %: С 64.72; Н
4.91.
Hexane was added to a residue after THF re-con-
densation. The formed precipitate of PhC≡CYbCl·
ClCPh3·THF was washed with hexane and dried under
vacuum. Yield 0.93 g (1.41 mmol, 70.5%). Found, %:
Yb 24.81; Cl 11.23. C31H28Cl2OYb. Calculated, %: Yb
26.91; Cl 10.76.
4-Phenylbut-3-yn-2-one. Suspension of 0.63 g
(1.0 mmol) of alkoxide VI, 4 mL of hexane, and 1 mL
of H2O was stirred at 50°С during 1 h. 0.49 g of dark-
brown compound was isolated, containing ~30% Pr,
along with hexane extract of methyl(phenylethynyl)
ketone. The ketone was purified via chromatography
on a silica gel column (eluent: petroleum ether –
dichloromethane, 1 : 1 v/v). 1Н NMR spectrum
(400 MHz, CDCl3), δ, ppm: 7.61–7.55 m (2Н), 7.49–
7.42 m (1H), 7.42–7.34 m (2H), 2.46 s (3H). 13С NMR
spectrum (101 MHz, CDCl3), δС, ppm: 184.75, 133.19,
130.87, 128.76, 120.06, 90.46, 88.41, 32.89.
Hexane was further re-condensed in a trap cooled
with liquid nitrogen, and ethanol was added to 1.0 g of
the oily residue. Polyphenylacetylene precipitated
(yield 0.25 g, 60%). IR spectrum, ν, cm–1: 3070, 3040,
1600, 1500, 1450, 750, 700 [7].
Triphenylmethyl radicals were detected in the
ethanolic solution by ESR, being in equilibrium with
the Ph6C2 dimer. After removal of ethanol, light-yellow
substance was isolated (yield 0.6 g, 2.5 mmol, 62.5%),
mp 145°С.
Reaction of 1.35 mmol of compound II with
16.8 mmol of acetyl chloride (molar ratio of 1 : 12)
was performed similarly in 15 mL of THF. The formed
Reaction of complex II with acetyl chloride. 1.07 g
(13.6 mmol) of acetyl chloride was added to a solution
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REACTIONS OF PHENYLETHYNYL CUPRATES OF LANTHANIDES
ACKNOWLEDGMENTS
2173
precipitate (0.41 g) mimeralized, and titration gave
concentrations of the formed Pr3+, Cu2+, and Cl¯ ions.
Yields of Pr and Cu were of 0.6 and 0.8 mmol (22 amd
20% with respect to the initial cuprate II), respectively.
Molar ratio of Cl¯ to Pr3+ was above 3 : 1.
This work was financially supported by Ministry of
Education and Science of Russian Federation.
REFERENCES
1. Bochkarev, L.N., Druzhkova, O.N., Zhiltsov, S.F.,
Zakharov, L.N., Fukin, G.K., Khorshev, S.Ya., Yanov-
sky, A.I., and Struchkov, Yu.T., Organometallics, 1997,
vol. 16, no. 4, p. 500. DOI: 10.1021/om9603777.
After washing out of THF and separation of the
precipitate, volatile compounds were re-condensed into
a trap cooled with liquid nitrogen. Hexane was added
to the oily residue. Brown complex VII precipitated
(yield 2.7 g, 1.95 mmol, 72.2%). Found, %: С 40.02;
2. Druzhkova, O.N., Cand. Sci. (Chem.) Dissertation,
Nizhni Novgorod, 2000.
Н 4.08; Сl 16.66; Cu 13.89; Pr 21.38. C46H52.5
·
3. Zhyl’tsov, S.F., Pimanova, N.A., and Druzhkova, O.N.,
Vestn. Nizhegorodsk. Univ. im. N.I. Lobachevskogo,
Ser. Kimiya, 2006, no. 1(5), p. 6.
Cl6.5O5Cu3Pr2. Calculated, %: С 39.83; H 3.79; Cl
16.65; Cu 13.75; Pr 20.35.
4. Tkachenko, L.I., Lisitskaya, A.P., Roshchupkina, O.S.,
Smirnov, V.A., and Aldoshin, S.M., Russ. Chem. Bull.,
2004, vol. 53, no. 6, p. 1168. DOI: 10.1023/
B:RUCB.0000042269. 52126.8d.
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and Zhyl’tsov, S.F., Russ. J. Gen. Chem., 2012, vol. 82,
no. 3, p. 504. DOI: 10.1134/S1070363212030231.
Volatile compounds were re-condensed from the
filtrate under vacuum at 30 °C into a trap cooled with
liquid nitrogen, after washing with hexane and
separation of the solid. The non-distilled liquid was
ester V (1.15 g, 1.85 mol per 1 mol of the initial
complex II).
6. Pimanova, N.A., Zhyl’tsov, S.F., and Druzhkova, O.N.,
Russ. J. Gen. Chem., 2003, vol. 73, no. 8, p. 1188. DOI:
10.1023/B:RUGC.0000007638.44196.89.
7. Zhyl’tsov, S.F. and Pimanova, N.A., Vestn. Nizhe-
gorodsk. Univ. im. N.I. Lobachevskogo, Ser. Kimiya,
2004, no. 1(4), p. 13.
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1970, vol. 11, no. 53, p. 4647. DOI: 10.1016/S0040-
4039(00)89398-3.
A mixture of 0.55 g of compound VII in 7 mL of
THF and 2 mL of water was heated during 2 h at 50°С.
The volatile products were re-condensed into a trap
cooled with liquid nitrogen. Hexane was added to the
oily residue. Brown precipitate was isolated from the
mixture (0.45 g), its composition being close to that of
PrCl3·3THF and containing ~30% of Pr.
After removel of hexane, 0.10 g of a mixture of 4-
phenylbut-3-yn-2-one and ester V was isolated from
the filtrate, compound V was identified by IR and
NMR spectroscopy. Formation of the ketone was due
to partial hydrolysis of ester V.
9. Zhyl’tsov, S.F., Dydykina, M.A., and Druzhkova, O.N.,
Russ. J. Gen. Chem., 2010, vol. 80, no. 9, p. 1767. DOI:
10.1134/S1070363210090082.
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1966, vol. 44, no. 6, p. 1231. DOI: 10.1139/v66-322.
11. Weissberger, A., Proskauer, E., Riddic, J., and
Тоорs, E., Organic Solvents, New York: Interscience
Publishers, 1955.
Reaction of complex I with acetyl chloride was
described elsewhere [9].
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 84 No. 11 2014