Resolution of racemic 3-aryloxy-1-nitrooxypropan-2-ols by lipase-catalyzed enantioselective acetylation
摘要:
Both (R)- and (S)-enantiomers of 3-aryloxy-1-nitrooxypropan-2-ols (R)-(-)-1, (S)-(+)-2 were prepared in high enantiomeric excess by lipase from Pseudomonas cepacia (Amano PS) or Pseudomonas fluorescens (Amano AK)-catalyzed acetylation of racemic alcohols la-g with vinyl acetate in n-hexane at 4 or 22 degreesC. The enantio selectivity of this transformation was dependent on the substitution pattern of the aryl ring with E-values ranging from 31 to 111. (C) 2001 Elsevier Science Ltd. All rights reserved.
Lipase-Catalyzed Kinetic Resolution of the Racemic Mixtures of 1-Aryloxy-3-Nitrato-and 1-Aryloxy-3-Azido-2-Propanols
作者:Beata Pchelka、Justyna Radomska、Jan Plenkiewicz
DOI:10.1080/00397919808004470
日期:1998.12
Abstract The racemicmixtures of 1-aryloxy-3-nitrato-2-propanols and 1-aryloxy-3-azido-2-propanols were resolved with moderate selectivity by the lipase-mediated acylation with vinyl acetate. The effects of the nature, position, and spatial requirements of the phenyl-ring substituents on the resolution degree were investigated.
Epoxides and aziridines are cleaved efficiently and regioselectively in the presence of zirconyl nitrate at room temperature to afford the corresponding beta-nitrato-alcohols and -sulfonamides, respectively, in high yields. (c) 2006 Elsevier Ltd. All rights reserved.
Efficient Regio- and Stereoselective Conversions of Oxiranes and Aziridines intoβ-(Nitrooxy)-Substituted Alcohols and Amines by Using Bismuth Nitrate
Oxiranes and aziridines efficiently undergo ring opening with bismuth nitrate at room temperature to furnish the corresponding β-(nitrooxy)-substituted alcohols and amines respectively. The conversions are highly regio- and stereoselective and afford the nitrooxy-compounds in excellent yields within a short period of time.
Both (R)- and (S)-enantiomers of 3-aryloxy-1-nitrooxypropan-2-ols (R)-(-)-1, (S)-(+)-2 were prepared in high enantiomeric excess by lipase from Pseudomonas cepacia (Amano PS) or Pseudomonas fluorescens (Amano AK)-catalyzed acetylation of racemic alcohols la-g with vinyl acetate in n-hexane at 4 or 22 degreesC. The enantio selectivity of this transformation was dependent on the substitution pattern of the aryl ring with E-values ranging from 31 to 111. (C) 2001 Elsevier Science Ltd. All rights reserved.