Patent Number: 6,841,679

Title: Process for the preparation of imidazopyridines

Abstract: A compound of the general formula (1), in which: Y denotes hydrogen, a halogen or a C.sub.1-4 alkyl group; X.sub.1 and X.sub.2 denote, independently of each other, hydrogen, a halogen, a C.sub.1-4 alkoxy, C.sub.1-6 alkyl, CF.sub.3, CH.sub.3 S CH.sub.3 SO.sub.2 or NO.sub.2 group; and R.sub.1 and R.sub.2 denote independently of each other, hydrogen or a C.sub.1-5 alkyl group, with the proviso that R.sub.1 and R.sub.2 do not both denote hydrogen, or a salt thereof, and is prepared by a multi-step process, the last step of which comprises reducing a compound of the general formula (6), in which Y, X.sub.1, X.sub.2, R.sub.1 and R.sub.2 are as defined above with an appropriate reducing agent, such as Zn, and, if desired, converting the compound of formula (1) thus obtained, into a salt. The products of this process are known to have useful pharmacological properties, e.g. as anxiolytics.

Inventors: Rey; Max (late of Wallisellen, CH), Rey-Papina; Heidedore Hisabeth (Wallisellen, CH), Rossler; Armin (Tengen, DE), Derungs; Giusep (Zurich, CH), Pak; Jae Kyoung (Zurich, CH)


International Classification: C07D 471/00 (20060101); C07D 471/04 (20060101); C07D 471/02 ()

Expiration Date: 01/12013