| 摘要 |
The present invention is directed to processes for the synthesis of morphinans, in particular, those of Formula 502: (see formula 502) In particular, a process for coupling a carboxylic acid compound with an amine compound to form an amide product that can then be isolated or the crude amide product can be cyclized to form a 3,4-dihydroisoquinoline. In one embodiment, the carboxylic acid contains a phenol moiety protected with a labile protecting group. The protected phenol reduces reaction times, simplifies work-up of the product, and reduces the amount of cyclizing agent, POCI3 that is necessary to form the 3,4-dihydroisoquinoline. |
