反应详情

In a first step as depicted in Scheme 2, an appropriately substituted phenyl derivative, for example, the known compound 2-methyl-5-(4-methylphenyl)-1,2,3,4-tetrazole, is brominated with, for example N-bromosuccinimide and light, to afford the corresponding 5-[4-(bromomethyl)phenyl]-2-methyl-1,2,3,4-tetrazole (A1). Intermediate (A1) is then reacted under basic conditions with an appropriately substituted cyclic amine derivative, for example, the known compound 4-piperidone hydrochloride monohydrate, to afford the corresponding 1-{[4-(2-methyl-1,2,3,4-tetrazol-5-yl)phenyl]methyl}piperidin-4-one (B1). Intermediate (B1) is then reacted under acidic conditions with, for example sodium cyanide, to afford the corresponding nitrile compound, 4-hydroxy-1-{[4-(2-methyl(1,2,3,4-tetrazol-5-yl))phenyl]methyl}piperidine-4-carbonitrile (C1). Intermediate (C1) is esterified under acidic conditions with, for example ethanol, to afford the corresponding ethyl 4-hydroxy-1-{[4-(2-methyl-(1,2,3,4-tetrazol-5-yl))phenyl]methyl}piperidine-4-carboxylate (D1). The Grignard of an appropriately substituted halophenyl derivative, for example 4-trifluoromethoxybromobenzene, is reacted with intermediate (D1) to provide compounds of formula I-B, wherein X and Y are, for example hydroxyl. Example 2, set forth below, provides detailed methods to how compounds of formula I (-B) shown in Scheme 2 were prepared.