Abstract
Reduction of CpMo(CO) 2 (syn-η 3 -CH 2 CHCHCOCH 3 ) (1) with NaBH 4 in MeOH produces (RR-(SS))-CpMo(CO) 2 (syn-C 3 -CH 2 CHCHCH(OH)CH 3 ) (2) with high diastereoselectivity. Treatment of the latter with 1 equiv of (CF 3 SO 2 ) 2 O in ether at -45°C stereospecifically generates the s-trans-η 4 -cis-pentadiene cationic complex 3, which adds nucleophiles regioselectively and stereospecifically at the α- or δ-carbons. The enolate of 1 generated with lithium diisopropylamide in THF undergoes diastereoselective aldol reactions. © 1990 American Chemical Society.