4-(Phenyl-(piperidin-4-yl)-amino)-benzamide derivaties and their use for the treatment of pain, anxiety or gastrointestinal disorders

A process for preparing a compound of formula I:

• or a slt thereof, wherein:
• R1 is selected from the group of phenyl, pyridinyl, thienyl, furanyl, imidazolyl, triazolyl, pyrrolyl, thiazolyl or pyridyl-N-oxide, and wherein each phenyl, pyridinyl, thienyl, furanyl, imidazolyl, triazolyl, pyrrolyl, thiazolyl or pyridyl-N-oxide is optionally substituted by 1,2 or 3 substituents independently selected from the group of straight and branched C1–C6 alkyl, NO2, CF3, C1–C6 alkoxy, chloro, fluoro, bromo, and iodo;
• comprising reacting a compound of formula II
• wherein PG is selected from the group of Boc, CBZ, benzyl and 2,4-dimethoxybenzyl, with N, N-diethyl-4-bromobenzamide, using a palladium catalyst, in the presence of a base, to give a compound of formula III:
• which is thereafter deprotected, and the deprotected product is alkylated with a compound of the formula of R1—CHO and the alkylated product is hydrolyzed to form the compound of formula I or a salt thereof.