Reactions of nickelocene with sodium in the presence of terminal alkenes

A novel reduction of nickelocene with metallic sodium in the presence of I- pentene and l-hexene was studied. It was found that two products of alkene activation were formed. The first one was a (mu(3)-hydrido)-(mu(3)-alkyridy ne)-trinickel cluster (1) and the second one a (mu(3)-alkylidyne)-trinickel cluster (3). Both types of clusters were characterised by spectroscopic me thods and by single-crystal X-ray diffraction measurements. The first clust er crystallised from hexane in a monoclinic system in the C2/c space group and the second one from methanol, also as a monoclinic system in the P2(1)/ c space group. (C) 2000 Elsevier Science S.A. All rights reserved.