A chemoenzymatic synthesis of a series of 2-hydroxy-5-nitro-4-substituted esters is described that uses two biotransformations in a single-pot process in which a kinetic resolution/reduction occurs. The products are valuable intermediates for the preparation of 4-substituted prolines and 5-substituted 3-hydroxypiperidinones as illustrated by the preparation of (2R,4R)-4-methylproline and (3S,5R)-3-hydroxy-5-methylpiperidinone.
Chemoenzymatic syntheses of cis- and trans-3-hydroxy-5-methylpiperidin-2-ones
作者:Stuart R Crosby、Martin J Hateley、Christine L Willis
DOI:10.1016/s0040-4039(99)02069-9
日期:2000.1
An approach to the enantioselective synthesis of cis- and trans-3-hydroxy-5-methylpiperidin-2-ones from racemic methyl 4-methyl-5-nitro-2-oxopentanonate 8 is described via the first example of a lactate dehydrogenase catalysed combined kinetic resolution and reduction of a 2-oxo acid. In an alternative approach, stereoselective conjugate addition of nitromethane to a crotonyl camphorsultam gave access