Microbial stereodifferentiating reduction of (.+-.)-4-methyl- and (.+-.)-6-methyl-1-oxo[2.2]metacyclophanes and revision of the absolute configuration of 4-substituted [2.2]metacyclophanes
Microbial stereodifferentiating reduction of (.+-.)-4-methyl- and (.+-.)-6-methyl-1-oxo[2.2]metacyclophanes and revision of the absolute configuration of 4-substituted [2.2]metacyclophanes
MICROBIAL STEREODIFFERENTIATING REDUCTION OF (±)-4-METHYL-1-OXO[2.2]METACYCLOPHANE AND REVISION OF THE ABSOLUTE CONFIGURATION OF 4-SUBSTITUTED [2.2]METACYCLOPHANES
The (−)-Cotton effect indicates (pS)-configuration to (−)-4-methyl-1-oxo[2.2]metacyclophane (17) which was isolated from a culture solution of (±)-14 with Rhodotorula rubra, and the conversion of (−)-17 to (+)-4-methyl[2.2]metacyclophane (21) via 19 assigns (pR)-configuration to (+)-21, contrary to Schlogl’s proposal.