Process for the Preparation of Cycloheptapyridine CGRP Receptor Antagonists

Abstract

The disclosure generally relates to a process for the preparation of compounds of formula I, including synthetic intermediates which are useful in the process.

We claim: 
     
         1 . A compound of formula II, or a salt thereof, where Ar 1  is phenyl substituted with 0-3 substituents selected from the group consisting of cyano, halo, alkyl, haloalkyl, alkoxy, haloalkoxy, and alkylSO 2  and R 1  is hydrogen or trialkylsilyl, alkoxy, alkylcarbonyl, benzyl, benzoyl, and pivaloyl. 
       
         
           
           
               
               
           
         
       
     
     
         2 . The compound of  claim 1  where Ar 1  is 2,3-difluorophenyl and R 1  is hydrogen or a salt thereof. 
     
     
         3 . The compound of  claim 2  which is the dihydrochloride salt. 
     
     
         4 . The compound of  claim 1  where Ar 1  is 2,3-difluorophenyl and R 1  is triisopropylsilyl or a salt thereof. 
     
     
         5 . The compound of  claim 4  which is the dihydrochloride salt.