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A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Breaking bonds and breaking rules: inert-bond activation by [(iPr3P)Ni]5H4 and catalytic stereospecific norbornene
Junyang Liu1, Manar M Shoshani1, Kethya Sum1
1Department of Chemistry and Biochemistry, University of Windsor, Sunset Avenue 401, Windsor, ON, N9B 3P4, Canada. sjohnson@uwindsor.ca.
Abstract:
The facile carbon atom abstraction reaction by [(iPr3P)Ni]5H6 (1) with various terminal alkenes to give [(iPr3P)Ni]5H4(μ5-C) (2) occurs via a common highly reactive intermediate [(iPr3P)Ni]5H4 (3), which was isolated by the reaction of 1 with norbornene. Temperature dependent 1H and 31P{1H} NMR chemical shifts of 3 are consistent with a thermally populated triplet excited state only 2 kcal mol-1 higher energy than the diamagnetic ground state. Complex 3 catalyzes the dimerization of norbornene to stereoselectively provide exclusively (Z) anti-(bis-2,2'-norbornylidene).
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