Stereoselectivity of the Enzymatic Reduction of Aldehydic and Ketonic Carbonyl Groups in Planar Chiral Organomanganese Complexes

• Published in: Agricultural and biological chemistry Vol. 54; no. 7; pp. 1781 - 1789
• Main Authors: Yamazaki, Yoshimitsu, Uebayasi, Masami, Someya, Jun-ichiro, Hosono, Kuniaki
• Format: Journal Article
• Language: English
• Published: Tokyo Taylor & Francis 01.07.1990; Agricultural Chemical Society of Japan
• Subjects: Biological and medical sciences; Biotechnology; Chemical industry. Chemical engineering; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Rhodotorula rubra
• ISSN: 0002-1369
• DOI: 10.1080/00021369.1990.10870190

(±)-Tricarbonyl(η 5 -1-formyl-2-methylcyclopentadienyl)manganese (1) was optically resolved with horse liver alcohol dehydrogenase (HLADH) and two species of yeasts, Saccharomyces sp. H-1 and Rhodotorula rubra IFO 889. Usually, (1R)-1 was preferentially reduced to give (−)-alcohol 2 of ≥ 97% e.e. − 84% e.e. Ketone analogue (±)-tricarbonyl(η 5 -1-acetyl-2-methylcyclopentadienyl)-manganese (4) was reduced by the yeasts. The major product by S. sp. H-1 was the (1S,2R,1′S)-(+)-alcohol (5) (≥ 98% e.e.) and the minor product, the (1R,2S,1′S)-(−)-alcohol (6) (86% e.e.). R. rubra gave only the latter alcohol (≥ 99 % e.e.). The Stereodifferentiation mechanism for these bioreductions is discussed in terms of the Prelog rule. The mechanism for HLADH reduction was examined with computer graphics.