X-Ray diffraction studies on catalysis: crystal structure of di-µ-trifluoroacetato-bis[(2-methylallyl-3-norbornyl)nickel(II)] and comparison with related nickel(II) and palladium(II) complexes

Abstract

The crystal structure of the title compound (III) has been determined from diffractometer data (1 888 non-zero reflections) by the heavy-atom method and refined by least-squares to R 0.070. Crystalts are monoclinic, space group P2₁/c,a= 16.431 (3), b= 9.954(2), c= 16.614(3)Å, β= 92° 32′(2′),Z= 4. The structure is compared with those of the related nickel [(I) and (II)] and palladium complexes, (IV), in view of their relevance to norborn-ene polymerization catalysed by π-allyl nickel carboxylates. The molecular configuration is considered to be a key factor in the formation of mononuclear species, which are the active intermediates in the propagation reaction.