I- catalyzed cascade annulation of 2-(pyridin-2-yl)acetate derivatives with N , N- dimethylenamine 2 ketones: Site-selective synthesis of functionalized indolizines

A novel synthesis method was developed for developing functionalized indolizines. In this reaction, 2-(pyridin-2yl)acetate derivatives and N , N -dimethylenamine ketones were used as substrates. All these processes were enabled by heating a mixture of starting materials in toluene and in the presence of I 2 under air. Cascade reaction resulted in the formation of two bonds and cleavage of one bond in one pot. Consequently, a number of functionalized indolizines were produced via a cascade reaction. This protocol can be used to synthesize functionalized unsymmetrical 2,4-diarylpyridines. Moreover, it is suitable for combinatorial and parallel syntheses of indolizines derivatives in a one -pot reaction and it is not a tedious multi -step reaction.