The enamines were prepared by condensation of aldehydes with Et2NH for the first time and reacted with CH2=CN to give corresponding γ -formoyl nitriles.it was discovered by the auther that γ-formoyl nitriles could isomerizate to 5-alkyl-3,4-dihydro-2-pyridones with high yield in the presence of organotin. the structures of new compounds were comfirmed by elemental analysis. IR, 1H NMR and MS. the catalytic activity of three kinds of organotin(BuSnO3/2, cat.1; Bu2SnO, cat2; Bu3SnF, cat.3) were compared .the cat.1 was studied in catalyst quantity used, reaction temperature and reaction time .the results indicated that through compared as catalyst. Organotins were better than alumina or anhydrous hydrochloride for the isomerization of γ-formoly nitriles.

Key words: CATALYST, PYRIDINONE, NITRILE, FORMYL, ALKYL, ISOMERIZATION, ORGANITIN