Patent ID: 7511154

Claim:
A process for the preparation of bipyrrolidinyl compounds of formula I wherein * signifies an asymmetric center with an (R) or (S) configuration and X represents chlorine, bromine or iodine; comprising: step 1) coupling the compound of formula II wherein * is as defined above with a compound of formula X(CH 2 ) 2 CH(X)COX wherein X is independently of each other chlorine, bromine or iodine; and subsequent cyclizing the compound of formula II in the presence of a base to obtain a compound of formula III wherein * and X are as defined above; step 2) reacting the compound of formula III with triphenylphosphine to obtain the phosphonium salt of formula IV wherein * and X are as defined above; and step 3) reacting the phosphonium salt of formula IV with di-tert.-butyl-dicarbonate under hydrogenation conditions to obtain the compounds of formula I.