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Molecular Structure of a Bridged cis-Bis(-allyl)nickel System.

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giving dimers to pentamers in the presence of similar Ni(0)
c o m p l e ~ e s ~ ~An
- ~ ]intermediate
.
with a ligand system
consisting of three allene moleculeswas recently described[?
In the present communication we report findings that led
eventually to a complete structure analysis of such an intermediate by three-dimensional X-ray methods.
Our studies on bis(tri-2-biphenyly1phosphite)nickel ( I )
have shown that this complex containing coordinately
unsaturated nickel(0) can be used to trap intermediates in
the oligomerization of allene.
in 90-95% yield. At 60°C this triene is formed catalytically
on the L,Ni(O) system. It is not possible to decide whether
the allene molecules are already joined in (4) or whether
such linkage actually happens on displacement. A complex
of ( 5 ) corresponding to (6) is probably present which is
possibly formed oia a n-ally1 intermediate that is produced
in an equilibrium similar to that found for a propylene-Nil
complex[''] :
Allene reacts with ( I ) (3 : 1) in toluene at 20°C to give an
orange crystalline product ( 2 a ) of composition C,H,,NiL
[L =(C,H,-o-C,H,O),P], which reacts quantitatively with
triphenylphosphane or carbon monoxide to yield 1,2,4-trimethylenecyclohexane (3).The 'H-NMR spectrum of ( 2 4 ,
which resembles that of the analogous Pd complex[71,
indicates the presence of a free C=C bond and of a cisbis(a-ally1)nickel system : T = 5.3 (1H), 5.6 (1 H), 7.40 (2H),
7.56 (2H), 7.63 (2H) [8.60d (2H); J = 1 0 . 4 H ~ ] , [8.68d
(2H); J=9.7 Hz].
A completely analogous preparation yields the corresponding compound (2 b ) , containing tricyclohexylphosphane
as additional ligand, whose structure was proved by the
'H-NMR spectrum-T=4.84 (IH), 5.26 (1 H), 6.90 (2H),
7.05 (4H), [8.13d (2H);J=lOHz], [8.21d(2H);J=9Hz]
and by X-ray structure analysis[8!
(6) corresponds to the complex formed from ( I ) and
butadiener6].
The simplest intermediate was found in the reaction of ( I )
with 1,2-~yclononadiene
(1 :1) in which a cyclononadiene.
NIL, complex (7) is formed.
We assume that (2) is formed in a multi-step reaction proceeding via the following intermediates :
1,2-Cyclononadiene is displaced unchanged from (7) by
triphenylphosphane. At 60°C, however, catalytic oligomerization with ( I ) occurs; mass spectrometry shows the
product to contain trimers to hexamers.
Received: September 15,1971 [Z 542a IE]
German version: Angew. Chem. 84, 120 (1972)
[I]W Brenner, P . Heimbach, H . J . Hey, E. 19: Miiller, and G . Wilke,
Liebigs Ann. Chem. 727, 161 (1969).
[2] R. E. Benson and R. V Lindsey, J. Amer. Chem. SOC.81,4247 (1959).
[3] F . W! Hoouer and R.
I/: Lindsey,
J. Org. Chem. 34, 3057 (1969).
[ 4 ] S . Otsuka, A . Nakamura, K . Tani, and S. Ueda, Tetrahedron Lett.
Intermediate ( a ) corresponds to a LNi-bis(o1efin)complex
in which two allene molecules are bonded, as in an analogous
bis(ethy1ene)system['], through one C=C double bond to
the LNi group in such a manner that the four carbon atoms
and the L.Ni group are practically coplanar. Carboncarbon coupling leads to ( b ) containing two C-Ni bonds
of which the metal-vinyl bond again adds to allene furnishing ( c ) . The ligand in (c) then inverts to give a cis-bis(nally1)nickel system containing formally five-coordinated
nickel. At elevated temperatures or in the presence of donors
the allyl groups in (2) couple and 1,2,4-trimethylenecyclohexane (3) is liberated. (2) contains asymmetric allyl
groups[81;and in particular that lying opposite the "exo"
methylene group should be written as having a C=C bond
and a C-C bond.
Reaction of ( I ) with 1,l-dimethylallene (1:2) in toluene
follows a different course to yield, at 20°C, a pale yellow,
sparingly soluble substance ( 4 ) having the composition
C,,H,,NiL, [L=(C,H,-o-C,H,O),P],
which reacts with
carbon monoxide at - 78 "C or with triphenylphosphane
at 80°C to give 2,5-dimethyl-3,4-dimethylene-l-hexene
(5)
Angew. Chem. internat. Edit. 1 Vol. I 1 (1972) 1 N o . 2
1969,297.
[5] S. Otsuka, A . Nakamura, S. Ueda, and K . Tani, Chem. Commun.
1971, 863.
[6] M . Englert, P . W Jolly, and G . Wilke, Angew. Chem. 83,84 (1971);
Angew. Chem. internat. Edit. 10, 77 (1971).
[7] 7: Okamoto, E Sakakitara, and S . Kunchika, Bull. Chem. SOC.Jap.
43, 2658 (1970).
[S] B. L . Barnett, C. Kriiger, and E-H. n a y , Angew. Chem. 84,120
(1972); Angew. Chem. internat. Edit. 11, 137 (1972).
[9] C. Kriiger and E-H. B a y , J. Organometal. Chem., in press.
[lo] H . Bonnemann, Angew. Chem. 82, 699 (1970); Angew. Chem.
internat. Edit. 9, 736 (1970).
Molecular Structure of a Bridged
cis-Bis(x-ally1)nickel System
By Bobby L. Barnett, Carl Kriiger, and Yi-Hung Tsay['l
Although the presence of cis-bis(n-ally1)nickelin equilibrium
with trans-bis(n-ally1)nickelhas been established by spec[*] Dr. C. Kruger, Dr. B. L. Barnett, and Dr. Y.-H. Tsay
Max-Planck-Institut fur Kohlenforschung
433 Mulheim-Ruhr, Lembkestrasse 5 (Germany)
137
troscopy, the former has defied all attempts at isolation and
characterization[']. The complex of nickel(0) with tricyclohexylphosphane and a trimerization product of allene as
ligands described in the preceding communication['] forms
triclinic c5ystals (unit cell : a = 14.443(9), b = 11.406(5), c =
13.151(9)A ; ~~=95.97f0.04,
p= 135.65k0.04, y = 100.32k
0.03"; space group P I ; Z = 2 ; d,,i,=1.195gcm-3) and
thus allows a three-dimensional X-ray structural analysis
to be performed.
The structure was solved by the heavy atom method with_
4533 diffractometer data collected in the space group B 1
(h= 1.5418)[3! It was found that one molecule of solvent
(toluene) is disordered about a center of symmetry in the
crystal lattice. Anisotropic least-squares refinement including isotropic hydrogen atoms and a disordered toluene
with partial occupancy factors gave a final R=8.9%.
Anomalous scattering of the heavy atoms was used in these
calcuIation~[~].
The structure of the complex is illustrated in Figure 1 ; the
geometry of the ligands of interest is shown in Figure 2
(distances in A, angles in ").
a square pyramid. The equation of the best plane through
C3, C7, Ni, P is
- 9 . 6 1 1~ 5 . 9 1 1 ~+ 5.1802
+ 5.425 = 0.
All cyclohexyl rings are equatorially bonded $and in the
chair form; the mean C-C bond length is 1.52 A, the mean
bonding angle 112".
The interesting asymmetry of the C-C bonds, which is in
the same sense in the two n-ally1 groups, seems to justify
formulation of the ligand as the possible canonical structure
(1).
The $1~1 group, conjugated with the extremely short
(1.28 A) double bond between C4 and C5, exhibits a
tendency towards symmetrization. The angle at C4 shows
the metal-ring system of the ligand to be highly strained.
The planes through the two allyl groups subtend a dihedral
angle of 29.6'.
Received: September 15,1971 [Z 542 b IE]
German version: Angew. Chem. 84,121 (1972)
23
C10 -P-Ni
C16 -P-NI
CZ2-P-NI
C10-P-C16
ClO-P-CZZ
C22-P-CI6
11L 0
115 7
112 5
1025
1083
102 8
cTB
P-C10 18L5
P-C16 1.864
F C 2 2 1.858
Absolute Configuration of a 1,2-Disubstituted
Ferrocene Derivative with Two Different Chiral
Substituents[']
Fig. 1
ca
"0
fi
C9-C7-C6 l l L
C ~ - C ~ - N I 75
C8-C7-C6 12L
CB-C~-NI 7L5
C9-C7-C8 1196
115 6
CZ-C~-NI 75
Cl-C3 NI 75
Fig. 2
As we have also found for numerous other examplesL5'the
coordination of the central atom is trigonal planar with
respect to the centers of gravity of the allyl groups; each of
the two rr-ally1 groups occupies a coordination position of
the nickel, as does the distorted tricyclohexylphosphane
tetrahedron. If the allyl group is considered to occupy two
coordination positions as a bidentate ligand there results
138
[I] H.Bijnnemann, B. BogdanooiC, and G. Wilke, Angew. Chem. 79,817
(1967); Angew. Chem. internat. Edit. 6, 804 (1967).
[ 2 ] M . Englert, P. W Jolly, and G. Wilke, Angew. Chem. 84,120 (1972);
Angew. Chem. internat. Edit. 11, 136 (1972).
131 Details of data collection and methods of calculation are given in:
C . Kriiger, J. Organometal. Chem. 22, 697 (1970).
[4] For Ni, P, C we used scattering curves given by D. T Cromer and
J . T Waber, Acta Crystallogr. 18, 104 (1965), and for H that given by
J . M c Wheeny: International Tables for X-Ray Crystallography (1962).
A list of structure factors and atomic parameters is available from the
authors (C. K.) upon request.
[5] P . W Jolly, K . Jonas, C . Kriiger, and K H . Tsay, J. Organometal.
Chem. 33,109 (1971); C . Kruger and E-H. Tsay, J. Organometal. Chem.,
in press.
By Linda F. Battelle, Robert Bau, George W Gokel,
Ray T Oyakawa, and Ivar Ugi"]
Neither the absolute configuration of a chiral 1,2-disubstituted ferrocene derivative, nor the configuration of a central
chiroid with a ferrocenyl ligand has hitherto been determined by X-ray methods. We wish to report the results of
such a determination.
The only optically active ferrocene derivative whose configuration has been established by X-ray crystallography
is (S)-3,1'-dimethylferrocene-1-carboxylicacid ( I ) ['I. Its
configuration has recently been correlated with that of
(S)-2-methylferrocene-l-carboxylicacid (2) by converting
(2) and (S)-3-methylferrocene-l-carboxylicacid (3) both
into the same l-methyl-2,3-tetramethyleneferrocene( 4 )
by sequences of eight steps[31,and by transforming (3) into
( I ) by a sequence of three reactions[41.By this and a pre[*] L. F. Battelle, M. A., Prof. Dr. R. Bau, Dr. G. W. Gokel,
R. T. Oyakawa, B. S.. and Prof. Dr. I. Ugi
Department of Chemistry
University of Southern California
Los Angeles, Calif. 90007 (USA)
Angew. Chem. internat. Edit. 1 Vo1. I 1 (1972) 1 No. 2
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