Synthesis of optically active vicinal fluorohydrins by lipase-catalyzed deracemization.
Three microbial lipases have been used to deracemize trans-2-fluorocycloalkanols 2 both by hydrolysis of the corresponding acetates 3 or chloroacetates 4 and by esterification of the fluorohydrins 2 using vinyl acetate and vinyl chloroacetate, respectively. Pseudomonas cepacia lipase was the most selective for the six- and the seven-membered-ring compounds, while the lipase from Candida rugosa was most useful for the eight-membered-ring compounds. Both lipases transform the (R)-enantiomers preferentially. In contrast the lipase from Candida antarctica hydrolyzed the esters of trans-2-fluorocyclohexanol 2a and esterified the fluorohydrin itself with very low enantiopreference for the (R)-isomers. The seven- and the eight-membered ring esters and the corresponding fluorohydrins were also transformed with low, but reverse, enantioselectivity.
Wölker
Dörthe
D
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstr. 40, D-48149 Münster, Germany.
Haufe
Günter
G
D000085:Acetates / Q000737:chemistry / Q000378:metabolism; D002175:Candida / Q000201:enzymology; D002384:Catalysis; D002942:Circular Dichroism; D004951:Esterification; D006844:Hydrocarbons, Cyclic / Q000138:chemical synthesis* / Q000378:metabolism*; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis* / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D015394:Molecular Structure; D011549:Pseudomonas / Q000201:enzymology; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014753:Vinyl Compounds / Q000737:chemistry / Q000378:metabolism
D000085:Acetates; D006844:Hydrocarbons, Cyclic; D006845:Hydrocarbons, Fluorinated; D014753:Vinyl Compounds; D008049:Lipase