Synthesis of imidazo [1,2-a] pyridine gem-amido vinyl sulfides, vinyl sulfoxides and vinyl sulfones. influence of the degree of oxidation of the sulfur on the stereoselectivity of the reaction

摘要

(E)-Stereoisomers of imidazo [1,2-a] pyridine gem-amido vinyl sulfoxides and vinyl sulfones are efficiently prepared by condensation of N,N-diethylphenylsulfinyl or N,N-diethylphenyl-sulfonylacetamide with imidazo [1,2-a] pyridine-2-carbaldehyde in the presence of NEt_3.