Process for preparation of 2-amino-6 (alkyl) amino-4,5,6,7-tetrahydrobenzothiazoles

摘要

A new process to obtain pramipexole and related products is described. The process involves the reaction of new compounds of formula (6), wherein R is hydrogen or acyl group, R3 and R4 are either the same and each of them represents an alkoxy group of 1-4 carbons or they together form a C2-C5 alkylenedioxy group or an oxo-group, with an alkylamine in the presence of a reducing agent or a hydrogen gas with hydrogenation catalyst. A process to obtain new compounds of formula (6) is also described.