ISSN 0036ꢀ0236, Russian Journal of Inorganic Chemistry, 2012, Vol. 57, No. 9, pp. 1232–1243. © Pleiades Publishing, Ltd., 2012.
Original Russian Text © M.A. Uvarova, E.V. Kushan, M.V. Andreev, A.O. Voroshilina, S.E. Nefedov, 2012, published in Zhurnal Neorganicheskoi Khimii, 2012, Vol. 57, No. 9,
pp. 1314–1325.
COORDINATION COMPOUNDS
Interaction of 3,5ꢀDimethylpyrazole with Cobalt(II) Carboxylates
Containing Coordinated 1,10ꢀPhenanthroline or 2,2'ꢀDipyridyl
M. A. Uvarova, E. V. Kushan, M. V. Andreev, A. O. Voroshilina, and S. E. Nefedov
Kurnakov Institute of General and Inorganic Chemistry, Russian academy of Sciences,
Leninskii pr. 31, Moscow, 119991 Russia
eꢀmail: snef@igic.ras.ru
Received January 21, 2012
Abstract—The reaction of Co3(
at room temperature yields L2Co2(
reaction of 1a
1b) with 3,5ꢀdimethylpyrazole gives a mixture of L2Co(Hdmpz)2(OOCBut)2 complexes
2a 3a 3b), and their yield is determined by the ratio of the initial reagents.
2b) and L2Co(Hdmpz)(OOCBut)2
As distinct from pivalates, for cobalt(II) phenanthrolineꢀbenzoate, only the (Phen)Co(Hdmpz)2(OOCPh)2 comꢀ
plex ( ) has been isolated. The structures of the synthesized compounds have been determined by Xꢀray crysꢀ
μ
ꢀOOCBut)6(NEt3)2 with 1,10ꢀphenanthroline or 2,2'ꢀdipyridyl in benzene
ꢀOH2)(
ꢀOOCBut)4 complexes (L2 = Phen (1a) and Dipy (1b)). The
μ
μ
(
(
,
( ,
4
tallography.
DOI: 10.1134/S0036023612090215
Deprotonation of coordinated pyrazole leads to the
IR spectra were recorded as KBr pellets on Specord
formation of pyrazolateꢀbridged biꢀ and polynuclear Mꢀ80 and NexusꢀNicolet spectrophotometers in the
compounds, which have attracted much recent interꢀ range 400–4000 cm–1.
est in the context of the discussed analogies between
Xꢀray diffraction experiments were carried out using
threeꢀelectronꢀdonating pyrazolate and carboxylate
a routine technique on a Bruker SMART Apex II autoꢀ
anions [1–12].
mated diffractometer with a CCD detector (
λ
Mo
scan). The structures
ꢀOOCBut)6(NEt3)2 were calculated with the SHELXTL PLUS program
,
Previously, it was shown that, owing to deprotonation graphite monochromator,
of Hdmpz, the reaction of Со3(
ω
μ
with 3,5ꢀdimethylpyrazole (Hdmpz) under mild condiꢀ package (PC version). The structures were refined
tions (benzene, room temperature) yields almost quantiꢀ with the SHELXTLꢀ97 program package [18, 19].
tatively pyrazolateꢀbridged binuclear complex Co2( ꢀ
μ
The crystal data and refinement details are listed in
Table 1, and the atomic coordinates and selected bond
lengths and bond angles in the complexes studied are
presented in Tables 2–11. Complete tables of atomic
coordinates, bond lengths, and bond angles were
deposited with the Cambridge Structural Database
(CCDC 891697–891701).
dmpz)2(OOCBut)2(Hdmpz)2 [13–15]. When an elecꢀ
tronꢀwithdrawing phenyl substituent is substituted for
the electronꢀdonating tertꢀbutyl substituent in the carꢀ
boxylate anion, the analogous reaction yields only the
mononuclear complex Co(OOCPh)2(Hdmpz)2, in
which the coordinated pyrazole can be deprotonated
with cobalt(II) acetate to give the binuclear pyrazolateꢀ
L2Co2(
µ
ꢀOH2)(
ꢀOOCBut)4 (L2 = Phen (1a), Dipy
µ
bridged complex Co2( ꢀdmpz)2(OOCPh)2(Hdmpz)2
μ
(1b)). Aqueous phenanthroline (0.12 g, 0.6 mmol) was
[16, 17].
added to a solution of 0.2 g (0.2 mmol) of Со3(μꢀ
In the present work, we consider structural features
of the products of the reactions of Hdmpz with
cobalt(II) pivalate or benzoate containing, as distinct
from monodentate triethylamine (which can also act
as a proton acceptor), strong bidentate donors, 1,10ꢀ
phenanthroline and 2,2'ꢀdipyridyl.
OOCBut)6(NEt3)2 in 20 mL of benzene. The resulting
red solution was concentrated to 10 mL and kept at
+5 С for 24 h. The resulting orange crystals were sepꢀ
°
arated from the mother solution by decantation,
washed with hexane, and dried in an argon flow. The
yield was 0.21 g (84%).
For Co2C40H54N4 (powder) anal. calcd. (%):
C, 56.34; H, 6.38; N, 6.57. Found (%): C, 56.98;
H, 6.29; N, 6.51.
EXPERIMENTAL
All operations dealing with the synthesis and isolaꢀ
tion of complexes were carried out in a pure argon
atmosphere with the use of dry solvents.
IR (KBr) (
ν
, cm–1): 3437 m, 2954 m, 2922 w, 1600 s,
1516 s, 1481 s, 1455 w, 1411 s, 1367 m, 1356 m,
1232
Uvarova
