Chemistry of molybdenum complexes with (triphenylmethyl)allene

Abstract

The cationic allene complex [Mo(η⁵-C₅H₅)(CO)₃(η²-CH₂CCHCPh₃)]BF₄1, was converted into the dihydronaphthyl complex [Mo(η⁵-C₅H₅)(CO)₃(C₁₀H₇Ph₂)] in the presence of KSCN as the major product. When the reaction was carried out at high concentration, the allylic complex [Mo(η⁵-C₅H₅)(CO)₂{η³-CH₂C(COC₁₀ H₇Ph₂)CHCPh₃}] was isolated as a minor product. Reaction of allene with the dihydronaphthyl complex also induced insertion of CO followed by C–C coupling to give the allylic complex [Mo(η⁵-C₅H₅)(CO)₂{η³-CH₂C(COC₁₀H₇Ph₂)CH₂}]. In CHCl₃ migration of the organic moiety on Mo in the dihydronaphthyl to the C₅H₅ ligand occurred giving [MoCl{η⁵-C₅H₄(C₁₀H₇Ph₂)}(CO)₃]. In tetrahydrofuran and MeCN, similar reactions gave [MoH{η⁵-C₅H₄(C₁₀H₇Ph₂)}(CO)₃] and C₅H₅(C₁₀H₇Ph₂) respectively. Under thermolytic conditions [Mo(η⁵-C₅H₅)(CO)₂(PPh₃){C(O)C₁₀H₇Ph₂}] was also converted into [MoCl{η⁵-C₅H₄(C₁₀H₇Ph₂)}(CO)₂(PPh₃)]. The latter complex and [W(η⁵-C₅H₅)(CO)₃(C₁₀H₇Ph₂)] have been characterized by X-ray diffraction analysis.