128495-88-5Relevant academic research and scientific papers
A new and facile preparation of tert-butyl (3R,5S)-6-hydroxy-3,5-O-isopropylidene-3,5-dihydroxyhexanoate
Sun, Fenglai,Xu, Gang,Wu, Jianping,Yang, Lirong
, p. 2454 - 2461 (2008/03/13)
A facile method for the preparation of tert-butyl (3R,5S)-6-hydroxy-3,5-O-isopropylidene-3,5-dihydroxyhexanoate is described by a chemoenzymatic approach. In this method, one hydroxyl stereocenter at C5 is obtained with a high ee value (up to 98.0%) via an enzymatic transesterification resolution of l-chloro-3-(4-methylbenzyloxy)-2-propanol. The other hydroxyl stereocenter at C3 was built with 98.0% de, by acid-hydrolysis of a 1,3-diol-acetonide syn/anti-10. It is noteworthy that the reduction of β-hydroxy ketone 8 with sodium borohydride can be carried out smoothly in aqueous isopropyl alcohol with a high diastereomeric ratio syn/anti (drs:a) of 4.0:1.
Enzymes in Organic Synthesis: Synthesis of Highly Enantiomerically Pure 1,2-Epoxy Aldehydes, Epoxy Alcohols, Thiirane, Aziridine, and Glyceraldehyde 3-Phosphate
Pederson, Richard L.,Liu, Kevin K.-C.,Rutan, James F.,Chen, Lihren,Wong, Chi-Huey
, p. 4897 - 4901 (2007/10/02)
This paper describes a chemoenzymatic procedure for the synthesis of (R)- and (S)-glycidaldehyde diethyl acetal (4 and 5). 2-Acetoxy-3-chloropropanal diethyl acetal (1c) was enantioselectively hydrolyzed by LP-80 lipase to give (S)-3-chloro-2-hydroxypropanal diethyl acetal (2c) and the unreacted acetate (3c), both in >95percent calculated yield and >98percent ee.Both products were subsequently converted to epoxides 4 and 5, respectively.Resolutions of 2-acetoxy-1-(benzyloxy)-3-chloropropane (11a) and 3-(allyloxy)-2-acetoxypropyl p-toluenesulfonate (14b) were similarly carried out to give the corresponding optically active 2-hydroxy and 2-acetoxy derivatives in 90percent and >95percent ee.These products were subsequently converted to the corresponding 1,2-epoxides.Nucleophilic opening of epoxide 4 was exemplified by the syntheses of (R)-3-azido-2-hydroxypropanal and D-glyceraldehyde 3-phosphate.Conversion of the chiral epoxides to thiirane and aziridine was also described.
