Synthesis and structure of [(η 5-C 5Me 5)WCl 2(μ-H)] 2. A dinuclear tungsten hydride with a double bond formed from the reaction of BH 3THF with (η 5-C 5Me 5)WCl 4

Abstract

The reaction of limited quantities of BH 3THF with Cp*WCl 4, Cp*=η 5-C 5Me 5, leads to the formation of [Cp*WCl 2(μ-H)] 2 and BH 2Cl in good yield. Structural characterization by spectroscopic and crystallographic techniques reveals the presence of two Cp*WCl 2 fragments in a transoid arrangement connected by a formal WW double bond ( d WW=2.5150(5) Å) bridged by two hydrogen atoms. Reaction of [Cp*WCl 2(μ-H)] 2 with additional BH 3THF leads ultimately to Cp* 2W 2B 5H 9, thereby providing information on the role of [Cp*WCl 2(μ-H)] 2 as an intermediate in the formation of Cp* 2W 2B 5H 9 from the reaction of Cp*WCl 4 with an excess of BH 3THF.