Pyrrolidine derived (S)-lactamide auxiliaries mediate a highly diastereoselective coupling reaction between racemic α-halo acids and N-benzylethanolamine. The adducts are readily cyclized upon treatment with a catalytic amount of TsOH giving the above titled compounds in >90% ee. The 4-fluorophenyl substituted oxazinone thus formed is the key intermediate in the synthesis of a potent NK1 receptor antagonist.
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Organic Chemistry