Isovaleric Aldehyde in the Synthesis of 4-Isobutyl-Substituted Pyridme-2(1H)-thiones,4H-Pyrans,and 1,3-Cyclohexadiene

摘要

Cyclocondensation of isovaleric aldehyde with various CH acids [benzoylacetonitrile,malono-nitrile,cyanothioacetamide,4-hydroxycoumarin,resorcinol,3-phenylpyrazol-5(lH)-one,3-morpholinocroton-anilide] in the presence of amines yields isobutyl-substituted 4H-pyrans,1,3-cyclohexadiene,and pyridine-2(lH)-thiones.The latter compounds were used in the synthesis of substituted 2-pyridino thioethers and thi-eno[2,3-b]pyridine.