Partial reduction of electron-deficient pyridines
The partial reduction of electron-deficient pyridines is described herein. Mono- and disubstituted pyridines can be transformed into functionalized dihydropyridines using either Birch reduction conditions or sodium/naphthalene in THF. The compounds formed by these high-yielding reductive alkylation protocols have potential as synthetic intermediates, and we have shown that bicyclo compounds containing 6,5, 6,6, and 6,7 ring systems can be prepared in one step via a base-promoted cylization.
Donohoe
TJ
Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, U.K., and SmithKlineBeecham Pharmaceuticals, Old Powder Mills, Tonbridge, Kent. TN11 9AN, U.K.
McRiner
AJ
Sheldrake
P