1
240
A. Bernardi et al. / Inorganica Chimica Acta 362 (2009) 1239–1246
together with an extension of our previous work to other halides
such as bromine and iodine.
46.58; Cd, 5.78%. IR (acetonitrile, 293 K) m(CO): 2008(s), 1868(m)
ꢀ1
cm
.
The related compounds [NR
NEt , NBu ; X = Br, I], can be obtained following the same proce-
dure as above employing the relative [NR ] [Ni C(CO)17] and
4 5 4 2 4 4
] [HNi30C (CO)34(CdX) ] [NR = NMe ,
4
4
2
. Experimental
4
2
9
2
CdX salts.
2.1. General procedures
2.4. Synthesis of [NEt
4 5 2
] [H Ni32ꢀy
4
C (CO)36ꢀy(CdBr)] ꢁ 2MeCN (y = 0.22)
All reactions and sample manipulations were carried out using
standard Schlenk techniques under nitrogen and in dried solvents.
All the reagents were commercial products (Aldrich) of the highest
[NEt ] [HNi30C4(CO)34(CdBr) ] (1.72 g, 0.505 mmol) was stirred
4
5
2
in MeCN (30 mL) for 1 h; IR indicated that the penta-anion
5
ꢀ
purity available and used as received. The [NR
and [NR (CO)34(CdCl) [1] [NR
NMe (CH Ph); n = 3–6] salts have been prepared according to the
literature. The analogous [NR (CO)34(CdX) ] [NR
NEt , NMe , NMe (CH Ph); n = 3–6; X = Br, I] salts have been pre-
pared in similar way, employing CdX instead of
ꢁ xH
CdCl O. Analysis of Ni and Cd were performed by atomic
ꢁ 2.5H
4
]
2
[Ni
9
C(CO)17] [12],
[HNi30C4(CO)34(CdBr )]
(CO)34(CdBr )]
2
partially deprotonated to [Ni30C4
2
6
ꢀ
4
n
] [H6ꢀnNi30
C
4
2
]
4
= NEt
4
,
4
NMe ,
under these conditions. [NEt ]Br (0.446 g,
4
3
2
2.12 mmol) was, then, added, and the resulting suspension stirred
overnight. The solvent was removed in vacuum, the residue
washed with water (40 mL) and THF (40 mL), and finally extracted
in MeCN (20 mL). Precipitation by slow diffusion of diisopropyl
ether (60 mL) gave a dark-brown crystalline precipitate composed
4
]
n
[H6ꢀnNi30
C
4
2
4
=
4
4
3
2
a
2
2
O
2
2
absorption on a Pye-Unicam instrument. Analyses of C, H and N were
obtained with a ThermoQuest FlashEA 1112NC instrument. IR spec-
tra were recorded on a Perkin Elmer SpectrumOne interferometer in
of crystals of [NEt ] [H Ni
C4(CO)
36ꢀy
(CdBr)] ꢁ 2MeCN (y = 0.22)
4
5
2
32ꢀy
(yield 0.775 g, 42.3% based on Ni). The salt is soluble in acetonitrile,
DMF, DMSO, sparingly soluble in acetone, insoluble in less-polar
solvents.
2
CaF cells. Structure drawings have been performed with SCHAKAL99
[
13].
Calc. for C83.79H106BrCdN Ni31.78O35.78 (3842.14): C, 26.20; H,
7
2
.78; N, 2.55; Ni, 48.56; Cd, 2.93. Found: C, 26.08; H, 2.59; N,
2
.2. Synthesis of [NMe
4
]
4 2
[H Ni30C
4
(CO)34(CdI)
2
] ꢁ 2COMe
2
2.22; Ni, 48.72; Cd, 3.05%. IR (acetonitrile, 293 K) (CO): 2005(s),
m
ꢀ1
1
873(m) cm
.
CdI O (0.754 g, 2.06 mmol) was added in portions to a solu-
2
ꢁxH
2
tion of [NMe [Ni C(CO)17] (1.85 g, 1.59 mmol) in THF (30 mL)
with stirring. The mixture was left to react for 3 h, until all the start-
ing [NMe [Ni C(CO)17] was disappeared by IR monitoring and,
4
]
2
9
2.5. Synthesis of [NMe (CH Ph)] [HNi33ꢀyC4(CO)37ꢀy(CdCl)]ꢁ5MeCN
3
2
6
(y = 0.86)
4
]
2
9
then, the resulting dark-brown suspension was evaporated to dry-
ness. The residue was washed with water (40 mL) and THF (30 mL),
NaOH (0.58 g, 14.5 mmol) was added to
a solution of
[NMe (CH Ph)] [HNi30C4(CO)34(CdCl)2] (1.85 g, 0.551 mmol) in
3
2
5
II
II
in order to remove all Ni and Cd salts and minor quantities of low-
er nuclearity Ni–C carbonyl clusters, and finally extracted in ace-
tone (30 mL) resulting in a dark-brown solution of the target
MeCN (30 mL) and the resulting suspension stirred overnight be-
fore filtration. The solvent was removed in vacuum from the fil-
trate, the residue washed with water (40 mL) and THF (40 mL),
and finally extracted in MeCN (20 mL). Precipitation by slow diffu-
sion of diisopropyl ether (60 mL) gave a dark-brown crystalline
precipitate composed of crystals of [NMe (CH Ph)] [HNi
i
compound. Precipitation by slow diffusion of PrOH (60 mL) gave
a dark-brown crystalline precipitate composed of crystals of
[
NMe
4
]
4
[H
2
Ni30
C
4
(CO)34(CdI)
2
] ꢁ 2COMe
2
, (yield 1.15 g, 66.0% based
3
2
6
on Ni). The salt is soluble in acetone, acetonitrile, DMF, DMSO, spar-
ingly soluble in THF and alcohols, insoluble in non-polar solvents.
C4(CO)
37ꢀy
(CdCl)] ꢁ 5MeCN (y = 0.86) (yield 0.821 g, 38.0%
3
3ꢀy
based on Ni). The salt is soluble in acetonitrile, DMF, DMSO, spar-
2 2 4
Calc. for C60H60Cd I N Ni30O36 (3653.02): C, 19.73; H, 1.66; N,
ingly soluble in acetone, insoluble in less-polar solvents.
1
4
.53; Ni, 48.21; Cd, 6.16. Found: C, 19.92; H, 1.51; N, 1.37; Ni,
Calc. for C110.14H111CdClN11Ni32.14O36.14 (4201.81): C, 31.49; H,
2.66; N, 3.67; Ni, 44.90; Cd, 2.68. Found: C, 31.22; H, 3.85; N,
ꢀ1
8.05; Cd, 6.03%. IR (acetone, 293 K)
The related compounds [NR [H
NMe , NEt , NBu
procedure as above employing the relative [NR
CdX salts.
m
(CO): 2018(s), 1873(m) cm
.
=
4
]
4
2
Ni30
4
C (CO)34(CdX) ] [NR
2
4
3.42; Ni, 45.02; Cd, 2.79%. IR (acetonitrile, 293 K) m(CO): 1995(s),
ꢀ1
4
4
4
; X = Br, I], can be obtained following the same
[Ni C(CO)17] and
1860(m) cm
.
4
]
2
9
2
2.6. X-ray crystallographic study
2
.3. Synthesis of [NMe
4
]
5
[HNi30
C
4
(CO)34(CdBr)
2
] ꢁ 6MeCN
Crystal data and collection details for [NMe ] [H Ni30C4
4
4
2
(
CO)34(CdI)
2
] ꢁ 2COMe
2
,
[NMe
4
]
5
[HNi30
C
4
(CO)34(CdBr)
2
] ꢁ 6MeCN,
CdBr O (0.664 g, 2.44 mmol) was added in portions to a
2
ꢁ xH
2
[NEt ] [H Ni
C (CO)
36ꢀy
33ꢀy
(CdBr)] ꢁ 2MeCN
(y = 0.22) and
4
5
2
32ꢀy
4
solution of [NMe [Ni C(CO)17 (1.85 g, 1.59 mmol) in THF
4
]
2
9
]
[NMe (CH Ph)] [HNi
C4(CO)
(CdCl)] ꢁ 5MeCN (y = 0.86) are
3
2
6
37ꢀy
(
30 mL) with stirring. The mixture was left to react for 3 h, until
reported in Table 1. The diffraction experiments were carried out
4 2 9
all the starting [NEt ] [Ni C(CO)17] was disappeared by IR monitor-
on a Bruker APEX II diffractometer equipped with a CCD detector
ing and, then, the resulting dark-brown suspension was evaporated
to dryness. The residue was washed with water (40 mL) and THF
using Mo K
a radiation. Data were corrected for Lorentz polariza-
tion and absorption effects (empirical absorption correction SADABS
[14]. Structures were solved by direct methods and refined by full-
matrix least-squares based on all data using F [15]. Hydrogen
atoms were fixed at calculated positions and refined by a riding
model. All non-hydrogen atoms were refined with anisotropic dis-
placement parameters, unless otherwise stated.
)
II
II
(
30 mL), in order to remove all Ni and Cd salts and minor quanti-
2
ties of lower nuclearity Ni–C carbonyl clusters, and finally extracted
in acetonitrile (30 mL) resulting in a dark-brown solution of the tar-
get compound. Precipitation by slow diffusion of diisopropyl ether
(
60 mL) gave a dark-brown crystalline precipitate composed of
crystals of [NMe [HNi30 (CO)34(CdBr)
] ꢁ 6MeCN (yield 1.16 g,
4.7% based on Ni). The salt is soluble in acetonitrile, DMF, DMSO,
sparingly soluble in acetone, insoluble in less-polar solvents.
Calc. for C70 Cd 34 (3763.35): C, 22.34; H, 2.09; N,
.09; Ni, 46.79; Cd, 5.97. Found: C, 22.56; H, 1.92; N, 4.19; Ni,
4
]
5
C
4
2
6
2.6.1. [NMe ] [H Ni30C4(CO)34(CdI) ] ꢁ 2COMe
4
4
2
2
2
The asymmetric unit contains half of a cluster anion (located on
+
H
78Br
2
2
N
11Ni30
O
an inversion centre), two [NMe4] cations and one COMe2 mole-
cule. These crystals appear to be non-merohedrally twinned. The
4