179612-04-5Relevant articles and documents
Lipase catalyzed resolution of α-hydroxymethyl sulfones. Determination of absolute configuration by semiempirical calculation of CD spectra and verification by X-ray structure analysis
Gais, Hans-Joachim,Von Der Weiden, Ingo,Fleischhauer, Joerg,Esser, Josef,Raabe, Gerhard
, p. 3111 - 3123 (1997)
The Candida antarctica lipase catalyzed esterification of the hydroxymethyl sulfones rac-1a and rac-1b led to the isolation of ent-1a (92% ee) and 1b (≤99% eel, respectively. The acyloxymethyl sulfone ent-7a (≤99% ee) was obtained by the Candida antarctica lipase catalyzed hydrolysis of rac-7a. Not only Candida antarctica lipase but also Pseudomonas cepacia lipase showed the opposite enantiomer differentiation in the esterification of the methyl substituted alcohol rac-1a and the benzyl substituted alcohol rac-1b. The absolute configuration of ent-1a and 1b was determined by measurement of their circular dichroism and the calculation of the CD spectra of 1a and 1b by semiempirical methods. The configurational assignment was verified by X-ray structure analysis of 1b and ent-7a.
Preparation of enantiomerically pure α-hydroxymethyl S-tert-butyl sulfones by Candida antarctica lipase catalyzed resolution
Gais, Hans-Joachim,Von Der Weiden, Ingo
, p. 1253 - 1256 (1996)
Candida antarctica lipase (CAL; Novozym 435) catalyzed acylation of racemic methyl and benzyl substituted hydroxy sulfones rac-3a and rac-3d, respectively, with vinyl acetate either neat or in ether solvents proceeded with E-values of 18 and 49. For the CAL catalyzed hydrolysis of methyl substituted acetoxy sulfone rac-4a in an emulsion of phosphate buffer and methyl tert-butyl ether at pH 7.0 an E-value of 22 was found. Acetate (+)-ent-4a as well as alcohols (-)-3a and (-)-(S)-3d were obtained with ee-values of 99% on a gram scale.
