Patent ID: 7868029

Claim:
A process for the preparation of a 2-amino-4,5,6,7-tetrahydro-6-aminobenzothiazole 5a: or an enantiomer or a salt thereof, comprising the steps of: (a) reductively aminating a protected cyclohexandione 1p with an amine R 1 R 2 NH to yield a protected 4-amino-cyclohexanone 2p: wherein P is a protected ketone functionality, and wherein one of R 1 and R 2 is hydrogen and the other of R 1 and R 2 is n-propyl; (b) deprotecting the protected 4-amino-cyclohexanone 2p to yield an unprotected 4-amino-cyclohexanone 3a: (c) treating the unprotected 4-amino-cyclohexanone 3a with iodine and a thiourea H 2 N(C═S)NHR 3 , wherein R 3 is hydrogen or a C 1 -C 12 alkyl to yield the 2-amino-4,5,6,7-tetrahydro-6-aminobenzothiazole 5a or an enantiomer or a salt thereof.