(Bicyclo[2.2.1]hepta-2,5-diene)carbonyltrihalogenoruthenate(II) complexes

Abstract

The preparation of the first anionic ruthenium(II) diene complexes M[RuX₃CO(C₇H₈)]{M = Ph₃(PhCH₂)P⁺ or Cs⁺; X = Cl or Br; C₇H₈= bicyclo[2.2.1]hepta-2,5-diene (norbornadiene)}via cleavage of [RuCl₂CO(C₇H₈)]_n with halide ion are reported. Detailed ¹H n.m.r. and homonuclear decoupling studies indicate a structure with the carbonyl and a halide group co-ordinated cis to the diene. Reaction of the complex [RuCl₂CO(C₇H₈)]_n with Ph₄AsCl,HCl in acetone gives a mixture of inseparable products, but when heated under reflux only cis-(Ph₄As)₂[RuCl₄(CO)₂] is isolated.