Regioselective Negishi Carboaluminations

Significance

A zirconocene catalyst was discovered to perform Negishi carboaluminations with a variety of alkynes and electrophiles in high yields and excellent regioselectivities and stereoselecti­vities favoring the E-isomer (usually >99:1 E/Z). Tandem carboalumination-1,4-addition and carboalumination-C-C bond formation were also reported with high yields and regioselectivities. This methodology for the synthesis of the important coenzyme Q₁₀ was successfully extended.