title: Lipase TL-mediated kinetic tesolution of 5-benzyloxy-1-tert-butyldimethylsilyloxy-2-pentanol at low temperature: concise asymmetric synthesis of both enantiomers of a piperazic acid derivative.
abstract: Lipase TL-mediated kinetic resolution of (+/-)-5-benzyloxy-1-tert-butyldimethylsilyloxy-2-pentanol (5) at low temperature proceeded to give the corresponding (S)-alcohol 5 and (R)-acetate 6 in quantitative yields with high enantiomeric purity. The addition of bases such as pyridine, DMAP, 2,4- and 2,6-lutidines, or triethylamine considerably enhanced the rate of kinetic resolution. The alcohol (S)-5 and the acetate (R)-6 were converted to piperazic acid derivatives (R)- and (S)-3, respectively, via the intramolecular Mitsunobu reaction as a key step.
authors.affiliation: School of Pharmacy, Tokyo University of Pharmacy & Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Aoyagi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Tasuku
authors.initials: T
authors.lastname: Ueno
authors.forename: Mai
authors.initials: M
authors.lastname: Horiguchi
authors.forename: Koichi
authors.initials: K
authors.lastname: Takeya
authors.forename: Robert M
authors.initials: RM
authors.lastname: Williams
mesh_terms: D000588:Amines / Q000737:chemistry; D002175:Candida / Q000201:enzymology; D002851:Chromatography, High Pressure Liquid; D003080:Cold Temperature; D003640:Dealkylation; D006859:Hydrogen / Q000737:chemistry; D007202:Indicators and Reagents; D007700:Kinetics; D008049:Lipase / Q000737:chemistry*; D008968:Molecular Conformation; D009993:Osmium Tetroxide; D010084:Oxidation-Reduction; D000439:Pentanols / Q000737:chemistry*; D011724:Pyridazines / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: C481820:5-benzyloxy-1-tert-butyldimethylsilyloxy-2-pentanol; D000588:Amines; D007202:Indicators and Reagents; D000439:Pentanols; D011724:Pyridazines; D012821:Silanes; C014756:piperazic acid; D006859:Hydrogen; D008049:Lipase; D009993:Osmium Tetroxide