FUROPYRIDINES .22. ELABORATION OF THE C-SUBSTITUENTS-ALPHA TO THE HETERONITROGEN ATOM OF FURO[2,3-B]PYRIDINE, FURO[3,2-B]PYRIDINE, FURO[2,3-C]PYRIDINE AND FURO[3,2-C]PYRIDINE

The Grignard reaction of fused ring cyanopyridine derivatives 1a-d wit h methyl- and phenylmagnesium bromide yielded the corresponding acylpy ridine compounds 2a-d and 3a-d. Furopyridine N-oxides 4a-d were conver ted into the compounds having a phenyl group at the alpha-position to the ring nitrogen 5a-d. Reduction of 1a-d and the carboxylic esters 6a -d with diisobutylaluminium hydride yielded the corresponding amines 7 a-d and aldehydes 9a-d. The aldehydes were converted to nitroethanol d erivatives 10a-d by condensation with nitromethane and acrylic ester c ompounds 11a-d by the Wittig-Horner reaction with methyl diethyl phosp honoacetate.