FUROPYRIDINES .15. SYNTHESIS AND PROPERTIES OF ETHYL 2-(3-FURO[2,3-B]PYRIDYL), 2-(3-FURO[3,2-B]PYRIDYL), 2-(3-FURO[2,3-C]PYRIDYL) AND 2-(3-FURO[3,2-C]PYRIDYL)ACETATE

Ethyl 2-(3-furopyridyl)acetates 10a-d were synthesized from furopyridi n-3(2H)-ones 4a-d by the Wittig-Horner reaction with diethyl cyanometh ylphosphonate, hydrolysis and the subsequent esterification. Reaction of compounds 10a-d with lithium diisopropylamide (LDA) gave the corres ponding methylenelithiated intermediate, and the subsequent reaction w ith benzaldehyde, acetone and iodomethane afforded the methylene-alkyl ated product respectively, while N,N-dimethylacetamide did not give an y reaction product. The 2-position of 10a, b and d is alkylated by the lithiation with excess of LDA and the successive reaction with an ele ctrophile.