Biocatalytic asymmetric and enantioconvergent hydrolysis of trisubstituted oxiranes
摘要:
Asymmetric biohydrolysis of trialkyl oxiranes (+/-)-1a-3a using the epoxide hydrolase activity of whole bacterial cells proceeded in an enantioconvergent fashion and thus led to the corresponding (R)-configurated vicinal diols Ib 3b in Lip to 97% enantiomeric excess (e.e.) as the sole product. The mechanism of this enantioconvergence vas investigated by O-18-labelling experiments and it was found that both enantiomers were hydrolysed with opposite regioselectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.
Biocatalytic asymmetric and enantioconvergent hydrolysis of trisubstituted oxiranes
摘要:
Asymmetric biohydrolysis of trialkyl oxiranes (+/-)-1a-3a using the epoxide hydrolase activity of whole bacterial cells proceeded in an enantioconvergent fashion and thus led to the corresponding (R)-configurated vicinal diols Ib 3b in Lip to 97% enantiomeric excess (e.e.) as the sole product. The mechanism of this enantioconvergence vas investigated by O-18-labelling experiments and it was found that both enantiomers were hydrolysed with opposite regioselectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.
ISOMERIZATION OF OXIRANES TO ALLYLIC ALCOHOLS WITH DIALKYLBORYL TRIFLUOROMETHANESULFONATES
作者:Tan Inoue、Tadafumi Uchimaru、Teruaki Mukaiyama
DOI:10.1246/cl.1977.1215
日期:1977.10.5
Isomerization of oxiranes to allylic alcohols by treatment with dialkylboryl trifluoromethanesulfonates and tertiary amines is described. Several reactions proceed in regioselective manner.
Alkylation of 2-Substituted (6-Methyl-2-pyridyl)methyllithium Species with Epoxides
作者:James R. Vyvyan、Rebecca C. Brown、Brian P. Woods
DOI:10.1021/jo802267n
日期:2009.2.6
Substituted (6-methyl-2-pyridyl)methyllithium species were reacted with 1,2-epoxyoctane and 2-methyl-2,3-epoxynonane. The monosubstituted epoxide reacted efficiently with lutidyllithium and a number of 2-substituted (6-methyl-2-pyridyl)methyllithium derivatives. The trisubstituted epoxide gave low yields of adducts with all (2-pyridyl)methyllithium species studied. These results are discussed in the context of a proposed synthesis of cananodine.
Biocatalytic asymmetric and enantioconvergent hydrolysis of trisubstituted oxiranes
作者:Andreas Steinreiber、Sandra F. Mayer、Robert Saf、Kurt Faber
DOI:10.1016/s0957-4166(01)00256-7
日期:2001.6
Asymmetric biohydrolysis of trialkyl oxiranes (+/-)-1a-3a using the epoxide hydrolase activity of whole bacterial cells proceeded in an enantioconvergent fashion and thus led to the corresponding (R)-configurated vicinal diols Ib 3b in Lip to 97% enantiomeric excess (e.e.) as the sole product. The mechanism of this enantioconvergence vas investigated by O-18-labelling experiments and it was found that both enantiomers were hydrolysed with opposite regioselectivity. (C) 2001 Elsevier Science Ltd. All rights reserved.