Intermediate compounds for the preparation of
View Patent ↗Disclosed are novel amino acid derivatives of formula (I) and (II) processes for the preparation thereof, and their use in the preparation of trans-5-chloro-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenz[2,3:6,7]oxepino-[4,5-c]pyrrole.
1. A process for preparing the compound of formula A, in at least about 63% yield:
the process comprising;
(a) providing as substantially the only amino acid derivative present in the reaction mixture, at least one trans-amino acid derivative of formula I or formula II or a mixture of the trans-amino acid derivatives of formula I and formula II
or a salt thereof, and cyclizing the amino acid derivatives present in the reaction mixture in the presence of a reducing agent which is borane or lithium aluminum hydride, and an additive which is aluminum chloride, silica gel, aluminum oxide, sodium hydroxide or sodium acetate to give the trans-compound of formula A.