Vinylidene complexes of osmium(0) derived from 1-naphthyl- or 2-naphthyl-carbyne complexes by hydride addition to the naphthyl substituents. The crystal structure of Os(CC 10H 8)(CO) 2(PPh 3) 2

Abstract

When treated with lithium triethylborohydride, the cationic carbyne complexes [Os(–CR)(CO) 2(PPh 3) 2] +(R=1-naphthyl, 1; R=2-naphthyl, 2) form 3 and 4, respectively, which both have the formula Os(C 11H 8)(CO) 2(PPh 3) 2. NMR studies of these two isomeric vinylidene complexes show that the product derived from the 1-naphthyl carbyne cation involves attack at the naphthyl ring in the position para to the carbyne carbon to give 3, while that derived from the 2-naphthyl carbyne cation involves attack at the naphthyl ring in the position ortho to the carbyne carbon to give 4. The structure of 4 has been confirmed by an X-ray crystal structure determination. Addition of HCl to the vinylidene complexes 3 or 4 results in the formation of the corresponding naphthylmethyl complexes, Os(CH 2R)Cl(CO) 2(PPh 3) 2 (R=1-naphthyl, 5; R=2-naphthyl, 6).