NH4OH-promoted Crystallization Induced Dynamic Resolution of N-(S)-(1-Phenylethyl)-α-chloro-α-aryl Acetamides for Asymmetric Syntheses of α-Mercapto Carboxylic Acid Derivatives

All articles of this category NH 4 OH promoted crystallization induced dynamic resolution (CIDR) of configurationally labile α-chloro acetamides has been investigated. CIDR of N -( S )-(1-phenylethyl)-α-chloro-α-aryl acetamides 2-4 has been successfully used for the asymmetric preparation of α-chloro carbonyl functionality up to 97 : 3 diastereomeric ratio in 95% yield. As an application of this methodology we have shown a stereospecific substitution reaction of (α S )- 2 with KSAc for the asymmetric preparation of α-mercapto carboxylic acid derivative (α R )- 5 . asymmetric synthesis - chiral auxiliaries - kinetic resolution - carboxylic acids - thiols