Chemoenzymatic synthesis of enantiopure isopropyl (3R)- and (3S)-3-hydroxycyclohex-1-ene-1-carboxylates and their reduction to isomers of isopropyl 3-hydroxy-cyclohexane-1-carboxylate
摘要:
Reduction of an alpha,beta-unsaturated cyclic ketone with Geotrichum candidum affords the corresponding (S)-allylic alcohol, while enantiospecific oxidation of the corresponding racemic alcohols leases the (R)-enantiomer unchanged, giving access to both enantiomeric forms. Subsequent chemical reduction of the double bond of these homochiral allylic alcohol allows all isomers of the corresponding cyclohexanols to be obtained. (C) 2002 Elsevier Science Ltd. All rights reserved.
process has been developed for the iridium(I)‐catalyzed vinylic C−H borylation of α,β‐unsaturated esters with bis(pinacolato)diboron (B2pin2). These reactions proceeded in octane at temperatures in the range of 80–120 °C to afford the corresponding alkenylboronic compounds in high yields with excellent regio‐ and stereoselectivities. The presence of an aryl ester led to significant improvements in the
Ir(I)-catalyzed CâH borylation of 1-cycloalkenecarboxylic derivatives with bis(pinacolato)diboron affords various alkenylboronates with functional groups in excellent yields. This reaction was also used in a one-pot borylation/SuzukiâMiyaura cross-coupling procedure.
Chemoenzymatic synthesis of enantiopure isopropyl (3R)- and (3S)-3-hydroxycyclohex-1-ene-1-carboxylates and their reduction to isomers of isopropyl 3-hydroxy-cyclohexane-1-carboxylate
作者:Laure Fonteneau、Sandra Rosa、Didier Buisson
DOI:10.1016/s0957-4166(02)00152-0
日期:2002.4
Reduction of an alpha,beta-unsaturated cyclic ketone with Geotrichum candidum affords the corresponding (S)-allylic alcohol, while enantiospecific oxidation of the corresponding racemic alcohols leases the (R)-enantiomer unchanged, giving access to both enantiomeric forms. Subsequent chemical reduction of the double bond of these homochiral allylic alcohol allows all isomers of the corresponding cyclohexanols to be obtained. (C) 2002 Elsevier Science Ltd. All rights reserved.