_P.-Powell-auth.-Principles-of-Organometallic-Chemistry-Springer-Netherlands-1988

Mechanisms of industrial processes
5. Consider the following reactions:
NiBr 2 + 2CH 2 =CH-CH 2 MgCI ~ (C,H,) 2 Ni + 2MgCIBr
(C,H,) 2 Ni + 3CH 2 =CH-CH=CH 2 -----+ C 12 H 18 Ni + C 6 H 10
Et 2 0
[1]
[1] [2]
C 1 ,H 18Ni~ C 12H 18NiPPh,
[2] ---~ [3]
sco C 12 H 18 CO + Ni(C0) 4
[4]
The 1 Hn.m.r. spectrum of [1] in solutionat 2 73 K shows resonances (relative
to TMS) at 64.91 (multiplet), 3.78 (doublet) and 1.70 (doublet) with relative
intensities 1:2: 2; in addition there is another set of similar resonances at D 4.43
(multiplet), 3.5 7 (doublet) and 2.17 (doublet) also with relative intensities of
1:2: 2. The ratio of the total area of the first pattern to that of the second is
temperature dependent.
Comment on the above reactions and identify [1], [2], [3] and [4], giving
structures whenever possible. Interpret the n.m.r. data given for [1].
(University of Warwick).
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