PROCESS FOR THE PREPARATION OF SUBSTITUTED PYRIDINE

摘要

Synthetic method of 4-ethoxycarbonyl-6,7-dihydro-5H-1-pyrindine repregented by formula(I) is provided in this invention. Sodium alkoxide prepared by dissolving sodium in alcohol is reacted with ethylcyanoacetate, then reacted with 2-halocyclopentanone to yield (+-)-2-(1-ethoxycarbonyl-1-cyanomethyl)cyclopentanone of formula(III). Compound of formula(III) is reacted with potassium t-butoxide in the presence of ether solvent, then reacted with allyl halogen to produce (+-)-2-cyano-2-(cyclopentanon-2-yl)pent-4-en-carboxylic acid ethyl ester of formula(IV). Compound of formula(IV) is reacted with ozone to yield (+-)-2-cyano-2-(cyclopentanon-2-yl)butan-4-oxo-carboxylic acid ethyl ester of formula(V), then lastly compound(V) is reacted successively with hydroxylamine and phosphorous trichloride to yield 4-ethoxycarbonyl-6,7-dihydro-5H-1-pyrindine.