Abstract
BF 3 -catalyzed electrophilic addition of aldehydes to CpMo(CO) 2 (η 3 -6-R-cyclohexadien-1-yl) (R = H, Me, Ph) in cold toluene produced isolable Mo-η 4 -diene cationic salts (I). Demetalation of these salts by Me 3 NO in CH 2 Cl 2 gave functionalized cyclohexadiene compounds in good yields. The stereochemistry of this carbon-carbon bond forming reaction has been clarified. Methods to utilize these cationic salts (I) for stereoselective syntheses of highly substituted cyclohexene compounds are demonstrated. © 1993 American Chemical Society.