Treatment Of MO(CO)3(NCMe)3 with a-chloroacetophenone yields intermedi
ate aldol condensation products that can be trapped as stable cyclopen
tadienyl complexes. The reactions are highly stereoselective and give
predominantly one isomer of each product. CpMo(CO)2[eta3-CH2C(Ph)=CH(C
OPh)] and CPMO(CO)2[eta3-CH2C(Ph)CHC(Ph)=CH(COPh)] were isolated and c
haracterized by X-ray crystallography.