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Conversion of Ammonia into Ketimine LigandsЧa Simple Method for Synthesis of Ketimine Complexes.

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(COD)2Ni,which is sparingly soluble in tetrahydrofuran, goes
into solution and the diamagnetic adduct ( 2 ) crystallizes out
on cooling: in other words, an Li2Ni-olefin complex is formed
preferentially in this case too.
(COD)zN1+ 2 L i
(COD)zNiLi2.4 T H F ]
(COD)zNi + 2 L i I
4 THF'
Treatment of (2) with iodine regenerates bis(cyc1ooctadiene)NiO with formation of LiI. The complexed olefin of
(2) can be displaced unchanged as 1,5-cyclooctadiene by CO.
The 'H-NMR spectrum of (2) in [D8]-THF is temperature
dependent. At -40-C a signal appears, alongside others, at
T =4.59 which is assignable to the protons attached to a free
C O D double bond, which can also be recognized as a free
double bond from a band at 1635cm-' in the IR spectrum
(THF, 0-C). A coordination site of the nickel in ( 2 ) is clearly
occupied by a "Li2" Iigand instead of by a double bond.
A free double bond can no longer be detected in the ' H-NMR
spectrum at 0°C. It appears plausible that all four double
bonds of the two C O D ligands participate in bonding to
the nickel only on a time-average basis (fluctional system)
so that, as in ( I ), an 18-electron shell is also established
in complex (2).
(2) reacts particularly readily with monoolefins such as ethylene or dienes such as butadiene and 1.3-dimethylbutadiene
which displace the cyclooctadiene to form new complexes
while retaining the bimetal unit Li,Ni.
Received: July 10, 1973 [Z 924c IE]
G e r m a n version: Angew. Chem. 87.809 (1975)
Publication delayed a t author's request
[ I ] K.Fischrr, K . Jonas, a n d G. Wilkr, Angew. Chem. 85, 620 (1973): Angew.
Chem. internat. Edit. 12, 565 (1973).
[ 2 ] K . Fischer, K.Jonus. P. hli\huch, R . Srohhci. and G . U'ilkr. Angew. Chem.
R5. 1002 (1973): Angew. Chem. internat. Edit. 12. 943 (1973).
[3] B. Bugdanuiic: M . Kriinw, a n d G . Wilkr, Liebigs Ann. C'hem. 699, 1
( 1966).
[4] K. Jonos. Dissertation, Universitat Bochum 1968.
[S] Norr added iii proof ( O c t o b e r 16, 1975). Arrangement / / h i has meanwhile beeii confirmed by X-ray structure analysis (D.J . B r m r r and C Krii(/c,r.
to be published)
Conversion of Ammonia into Ketimine Ligands-a
Simple Method for Synthesis of Ketimine Complexes[']
By Dieter Sellrnann and Ernst Thal/rnair[*]
Complexes containing aldimine or ketimine ligands
R'R2C=NH (R', R 2 = H , alkyl or aryl) can be prepared from
metal compounds and ketimines, oximes, diazo derivatives
or other nitrogen compounds. Starting from ketimines one
is then limited to aromatic ketimines, which can be isolated
in substance P . y. diphenylmethanimine'21. As far as we know.
the condensation of ammonia complexes with carbonyl compounds has not been observed previously:
L,M - N H I
+ O=CR'R'
ketazine intermediates : ketazines from which hydrazine
can be liberated hydrolytically may be prepared by aerial
oxidation of ketiminesl", the direct synthesis o f the required
ketimines from free ammonia and ketones, however, is beset
with difficulties["].
We have found a simple synthesis of the ketimine skeleton
from complex-bound NH3 and ketones: (OC)SCrNH3( I )
with an excess of acetone in the presence of a drying agent
(MgSOJ affords the imine complex (2)['] in 75 yield.
+ H'O
This reaction could become important in respect of the
catalytic oxidation of ammonia to hydrazine by air ria
[*] Priv.-Doz. Dr. D. Sellmann a n d Dip].-Chem. E. Thallmair
Anorganisch-chemisches lnstitut der Technischcn Universitit
8 Munchen 2. Arcisstrasse 21 (Germany)
( I )
+ Acetone
56°C 4 h
+ H,O
(2) can also be obtained at room temperature; addition
of bases increases the reaction rate. We therefore assume
that the anion of ( I ) , [(OC)sCrNH,]-, takes part in the
formation of (2).
This type of reaction can be applied to other aliphatic
ketones, e. y. (OC)SCrNH=C,H,o (3) can be obtained from
( I ) and cyclohexanone in 78% yield after 5 h at 55°C.
No ketimine, but only polymolecular products therefrom
can be isolated when lower aliphatic ketones such as acetone
are condensed with free a m r n ~ n i a ' ~The
' . formation of (2)
and (3) shows that this condensation can be stopped after
the first step by use of complex-bound ammonia since the
ketimine skeleton that is unstable in the free state is stabilized
by the complex formation.
( I ) ( I .oOg. 4.8 mmol) is heated in acetone (30ml) together
with KOCH, (30mg) and MgS04 (2g) for 4 h at the boiling
point. After filtration and evaporation of the filtrate a yellow
oil remains, whence pure crystalline ( 2 ) (0.89g, 7 5 7 ) is
obtained by chromatography in pentaneltoluene (1 : 1 ) on S i 0 2
(column: 1 =SO, 0= 1.5cm: Merck silica gel 60, grain size
0.063-0.200mm) at -20°C.
Received: J u n e 12, 1975 [ L 269 IE]
German version: Angew Chem. X 7 . 772 11975)
Publication delayed at authors' request
CAS Registry numbers:
I I ) , 15228-27-0: ( 2 ) .28394-70-9: (31.2X294-78-2:acctone. 67-64-1: cyclohcuanone. 108-94-I : MgSOI. 7487-88-9
Reactions of Complex-bound Ligands. Part 17. Lecture a t Diisseldorf.
April 9. 1975. This work was supported hy the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen 1ndustrie.-Part 16: D. S d l i ~ i u i i i i and E. Kleirtscliinidt. Angew. Chem.. Angew Chem internat Edit..
in the press.
[?] .I ~~fi.\miu,
7: Osu. and S. Korla. Bull. Chem. Soc. Jap. 41. 373 (196X).
1.31 Cf. Tli. Kauffniunii. Angew. Chem. Xh, 321 11974): Angea. Chem. internat.
Edit IJ. 291 (1974).
[J] Cf. S. Purui. T h e Chemistry of the Carbon-Nitrogen Double Bond.
Wiley-Interscience. London 1970. p 61
[S] E 0. F i d i i ~ rand L. Kiioii.\\. Chem. Ber IOJ. 1262 (1970).
7-Oxanorbornadiene-3Oxaquadricyclane[* *I
By Horst Prinzbach and Horst Bahsch"]
Owing to the unavailability of the unsubstituted 7-heteronorbornadienes, the synthesis of 3-oxa- ( 2 0 ) and 3-azaquad-
Prof. Dr. H. Prinzbach and Dipl.-Chem. H. Babsch
Lehrstuhl fur Organische Chemie der Universitiit
78 k-reiburg, Albertstrasse 21 (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie. We a r e grateful to Dr. H . Fritz
for I 'C measurements. and t o Dr. M/ J . R i c h e r for some MS measurements.
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simple, ammonia, synthesis, method, ketimine, complexes, ligandsчa, conversion
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