A novel dynamic kinetic resolution accompanied by intramolecular transesterification: asymmetric synthesis of a 4-hydroxymethyl-2-oxazolidinone from serinol derivatives

Reaction paths of the one-pot reaction of (R)-2-(α-methylbenzyl)amino-1,3-propanediol () and 2-chloroethyl chloroformate with DBU giving (4S,αR)-4-hydroxymethyl-3-(α-methylbenzyl)-2-oxazolidinone ] (94% de) were investigated. Intermediates of this reaction, 2-chloroethyl (2S)- and 2-chloroethyl (2R)-3-hydroxy-2-[(αR)-α-methylbenzyl]aminopropyl carbonates and ], were synthesized individually. After the addition of DBU to the respective solution of the carbonate and that of in dichloromethane, the intramolecular transesterification between and and the diastereoselective intramolecular cyclization proceeded to afford in high diastereomeric excess. Therefore, two monocarbonates and were kinetically resolved by this cyclization during the intramolecular transesterification between and . We found that this process involved dynamic kinetic resolution accompanied by intramolecular transesterification.