δ-Keto Aminoacrylonitriles and δ-Keto Aminoenones from 1-Pyrrolines, Cyanoacetylenes, and Acetylenic Ketones

The ring-opening/functionalization of 1-pyrrolines by cyanoacetylenes or acetylenic ketones (20-80 degrees C, MeCN, H2O) affords delta-keto aminoacrylonitriles and.-keto aminoenones, mostly as the Z-isomers, in up to 85% yields. The synthesis involves C(2)-N bond cleavage in the intermediate hemiaminal resulting from the intermediate 1,3(4)-dipolar 1-pyrroline/acetylene complexes and water.

Automated summary

The ring-opening/functionalization of 1-pyrrolines by cyanoacetylenes or acetylenic ketones in suitable temperature and solvent conditions affords delta-keto aminoacrylonitriles and.-keto aminoenones with high yields. The synthesis involves C(2)-N bond cleavage in the intermediate hemiaminal resulting from the intermediate 1,3(4)-dipolar 1-pyrroline/acetylene complexes and water.