Polycyclic N-heterocyclic compounds.53 One step synthesis of imidazo[1,5-a]pyridine derivatives by the Vilsmeier reaction using N,N- dimethylarylamides

The versatile one step synthesis of 3-ary-1-(C-aryl-N,N- dimethylaminomethyleneamino)-7-chloro-2-methylimidazo[1,5-a]pyridin-2-ium chloride and their derivatives by the reaction of 2-pyridinecarbonitriles with N,N dimethylarylamides and phosphorus oxychloride under the Vilsmeier condition is described. The structures are based upon characteristic spectra and analytical data as well as X-Ray diffraction.