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Ethylenebis(phenylsodium)nickel.

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opposite each other relative to the cobalt atom. Free coordination sites on the lithium are occupied by ether molecules.
Characteristic for interactions between main group metals
and transition metals in complexes is the incorporation of
carbon atoms with formation of multicenter electron-deficient
bondsLz1
(cf. Fig. 1).
The most important structural characteristics in (3) are
multicenter bonds of the metals to the phenyl ring (C41)
and to the second C 8 unit of the molecule. Noteworthy are
the interactions between lithium and the B-C atoms of the
phenyl group(C42)[31aswell as the C 8 unit (C 12),and particularly the formation of a three-center bond with two different
metal atoms at the olefin carbon atom C 11 of the former cyclfoctenyl group. The Co--C bond to the C 11 atom (1.888 A )
is remarkably short.
E.xprrinienta1 procedure:
A stirred suspension of ( 1 )[41 (10.0g, 36.2mmol) in diethyl
ether (1S0ml) is treated at -30°C with a solution of LiChH5
(6.1g, 72.4mmol) in ether (100ml) and the whole warmed
to 20°C within 1 h. The color of the reaction solution gradually
changes from dark-brown to red. After further stirring for
1.5 h the solution is evaporated down to ca. 1 S0ml and cooled
to - S O T , whereupon gold-red crystals of (3) separate out.
Recrystallization from ether affords 8.5 g of the pure product,
which is best stored in an ethereal atmosphere at -30°C.
- _ _ ~
Rccei\ed: Ocroher 6 . 1 9 7 5 [Z 336 I & ]
G e r m a n version: Angew Chem 88. 50 (1976)
In ( 1 a ) the diethyl ether bonded to sodium can be replaced
by stronger n-donors such as tetrahydrofuran (THF) or
dimethoxyethane (DME) to give the crystalline complexes
( l b ) and ( I c ) etc.:
The composition of compounds ( I u ) , ( 1 b ) and (1 c ) follows
from the nickel and sodium content (determined titrimetrically
and by flame spectroscopy) and also by reaction of ( I ) with
carbon monoxide, whereby the ethylene is quantitatively liberated. The various n-donors (C1H5)20rT H F and DME in
( l a ) , ( 1 b ) and ( l c ) can be determined quantitatively by
gas chromatography after decomposition of the complex with
ethanol and distillation. The 'H-NMR spectrum of ( I a ) in
[D,]-THF shows two groups of signals for the phenyl protons
at T = 1.9 and 3.3 in the intensity ratio 4 : 6. The protons
of the ethylene bound to nickel are, like those in the lithium
complex (2) (T = 9.87)[", strongly shielded, and in ( I a ) give
rise to a singlet at r=9.58.
It follows from X-ray structural analysis of the ethylene
complex ( 1 b ) and the (alkali-meta1)nickel dinitrogen complexes
~
H . B ~ j w i m o i i u ,Angew. Chem. 85. I024 (1973): Angew. Chem. Int. Ed.
Engl. 12. 964 (1973).
, P. J. Rohrr-is. a n d Y - H . Tsni-. .I.
[ I ] K . Jwxr\. D. J . B i . o i i i ~ . C. K r
Am. Chem. SOC..in press.
131 J . J . Brooks a n d G . D. SIIIC~J.. J. A m Chem. Soc. 414. 7333 (1972):
J . J B r i d a . W.Rliiiie. a n d C . D. S t i i ( . k ~ihid.
.
94, 7339 (1972).
[4] S. Or,~ir/,na n d !M.Ro.s\r, J. Chem. Soc. A 1908.2630: W Ltwchic,. Dissertation. Universitlit Bochum 197 I:
H . L r l i d x h l , W:Lc,irdirc.. a n d E. Jausseri,
,I.Organoincul. Chein. 30. 407 (197 I ) .
[ { ( L l C G f - 1 5 ) ~ h l ) ? r , - 2 ( ~ C 1 M 5 ~ 2 0 ~ 2 131
-3J2
[I]
Ethylenebis(pheny1sodium)nickel
By
Kh.5
Jona.~"]
and
that all three compounds contain characteristic diphenylnickel
groups, which interact with the 71 system of the ethylene and
the nitrogen to give a trigonal array of these ligands. The
various interactions of the alkali metal atoms have tentatively
been ignored in this connection. Whereas only one (C,H 5)2Ni
group is coupled with the C2H, ligand in complex ( I h)[s"l,
In continuation of our studies on alkali-metal compounds
of nickel". 2 1 we have checked the reactivity of the (phenylsodium)nickel(o)system toward N213'as well as other multibonded partners, e. g. olefins. In this communication we report
on the complex ethyIenebis(pheny1sodium)nickel ( I ), for
which X-ray structural data are already a ~ a i l a b l e [ ~ " ~ .
Reaction of all-trans-i,S,9-~yclododecatrienenickel(0)~~~
(CDT-Ni') with a salt free NaC,H,/LiC,H,
mixture
(Na/Li=2-4:1)[31 in the molar ratio (NaC,H,+
LiC,H,)!Nio=2:1
and ethylene in diethyl ether leads to
in complexes f3)[5b1and (4)"' two (C,H5)2Ni groups are
the two compounds (NaC,H5)2NiC,H4[(C,H,)20], ( I u )
bonded side-on to the N, ligand via the two nickel atoms.
and (LiC,H 5)2NiC2H4(C2H5)20
(2). The previously known
Received: October 16, 1975 [Z 3.3721 IE]
complex (2) remains in solution, while the new sodium
German version. Angew. Chem. 88. 51 (1976)
complex ( I L I ) precipitates as an orange-red powder (yield
80-90 ",).
C A S Registry n u m b e r s :
CDT-Ni". 12126-69-1 : NaC,H,. 1623-99-0:
(NaC,H,),NiC,H,[(C,H,),0]2.
57774-32-0
[I]
r n (Ka(l,H5)2h I C zI14[ (Czff5 )20J2
+ n (LiCsH5)2NiC 2H4(C2 H 5 ) 2 0
i101
121
= 2-4 : 1
nitn = 1
mjii
_ _ _ [*] Dr. K . J o n a s
Max-Planck-lnstitut fur Kohlenforschung
433 Miilheim-Ruhr, Kalser-Wilhelm-Platz 1 (Germany)
[2]
+ cL)1
[3]
[4]
[5]
K . Jotiris. Angew. Chem. 85. 1050 (1973): Angew. Chem. Int. Ed. Engl.
12, 997 I 1973).
K. Fisrher, K . Jonas, P. Misbrich, R. Sruhha. a n d G. Wilke. Angew.
Chem. 85, I002 (1973): Angew. Chem. Int. Ed. Engl. I , 943 (1973).
K. J o f i u s , D. J . Bruirer. C . Kriiyrv, P J. Roberts, a n d Y.-H. Tsar. J .
A m Chem. Soc.. in press.
B. B ~ ~ & i m ~ i tM, . KrAtier, a n d G. Wilke. Justus Liebigs Ann. Chem.
6YY. 1 (1966).
a ) D. J. Braurr. C . Kriiyer, P. J . Aoherrs, a n d Y - H . Tsoi.. Anpel+. Chem.
X8. 52 (1976): Angew C h e m Int. Ed. Engl. 15. 4 8 j 1 9 7 6 ) : b) C Kriigcr
a n d Y - H Tior. ihid. 85. 1051 (1973). a n d 12. 998 (19731
41
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