CHIRAL ORGANOMETALLIC NADH MIMICS - PREPARATION AND X-RAY CRYSTAL-STRUCTURE OF RACEMIC (RS)-[FE(ETA-5-C5H5)(CO)(PPH3)(1-METHYL-1,4-DIHYDRONICOTINOYL)] AND HOMOCHIRAL(R)-(-)-[FE(ETA-5-C5H5)(CO)(PPH2(O-[(-)-MENTHYL]))(1-METHYL-1,4-DIHYDRONICOTINOYL)] AND ASYMMETRIC REDUCTION OF ETHYL BENZOYLFORMATE

The racemic complex (RS)-[Fe(eta-5-C5H5)(CO)(PPh3)(1-methyl-1,4-dihydronicotinoyl)] has been prepared and shown to function as a NADH mimic. An X-ray crystal structure revealed that one face of the 1,4-dihydronicotinoyl moiety is essentially blocked by the triphenylphosphine ligand. The homochiral complex (R)-(-)-[Fe(eta-5-C5H5)(CO)(PPh2(O-[(-)-menthyl])](1-methyl-1,4-dihydronicotinoyl)] possessing the sterically demanding chiral auxiliary [Fe(eta-5-C5H5)(CO){PPh2(O)-(-)-menthyl)}] at C-3 has also been prepared and shown to reduce ethyl benzoylformate to ethyl mandelate in 52% enantiomeric excess by a combination of steric and chelation control.