15 a 1: l mixture of Smlz and PhCHO, which presumably consists of the pinacol adduct (PhHC0) smI and SmI,, is equally effective as a catalyst (ca. 15 mol 5%) in reductions with benzaldehyde or isobutyraldehyde. 16 Whether the pinacolsamarium (II1) complex, Sml,, or the combination of the two is the active catalyst remains to be determined; however, we find Sm1," to be less efficient and SmCI, and Sm (acac), entirely ineffective as catalysts. ...