Patent ID: 7009078

Claim:
Process for preparation of compounds of formula I, wherein R 1 and R 2 are independently of one another H, C 1 –C 6 alkyl, C 1 –C 6 halogenalkyl, C 1 –C 6 alkoxy, C 1 –C 6 alkoxy-C 1 –C 6 alkyl, or C 1 –C 6 alkoxy-C 1 –C 6 alkyloxy, R 3 is C 1 –C 6 alkyl, R 4 is C 1 –C 6 alkyl, and R 5 is C 1 –C 6 alkyl, C 1 –C 6 hydroxyalkyl, C 1 –C 6 alkoxy-C 1 –C 6 -alkyl, C 1 –C 6 alkanoyloxy-C 1 –C 6 alkyl, C 1 –C 6 aminoalkyl, C 1 –C 6 alkylamino-C 1 –C 6 -alkyl, C 1 –C 6 -dialkylamino-C 1 –C 6 -alkyl, C 1 –C 6 -alkanoylamido-C 1 –C 6 -alkyl, HO(O)C—C 1 –C 6 -alkyl, C 1 –C 6 alkyl-O—(O)C—C 1 –C 6 alkyl, H 2 N—C(O)—C 1 –C 6 alkyl, C 1 –C 6 alkyl-HN—C(O)—C 1 –C 6 alkyl or (C 1 –C 6 alkyl) 2 N—C(O)—C 1 –C 6 -alkyl, comprising a) the reaction of a compound of formula II wherein R 6 is C 1 –C 6 alkyl, R 7 is C 1 –C 6 alkyl or C 1 –C 6 alkoxy, or R 6 and R 7 together are tetramethylene, pentamethylene, 3-oxa-1,5-pentylene or —CH 2 CH 2 O—C(O)— optionally substituted with C 1 –C 4 alkyl, phenyl or benzyl, with a halogenation agent in the presence of water, and optionally, an acid to form a compound of formula III, wherein X is Cl, Br or I, b) reaction of the compound of formula III with an azidation agent to form a compound of formula IV, c) thereafter reaction of the compound of formula IV with an amine of formula R 5 —NH 2 to form a compound of formula V, and d) for preparation of a compound of formula I, reduction of the azide group of the compound of formula V to form the amine group and then isolation of the compounds of formula I, optionally with the addition of a salt-forming acid.