Photocyclisation of enamides. Part IX. Syntheses of benzonaphthyridines by photocyclisation of N-pyridylcyclohex-1-enecarboxamides and pyridine-(N-cyclohex-1-enyl)carboxamides
Abstract
The N-pyridylenamides (Ia—c) were photocyclised to afford equimolar mixtures of cis- and trans-lactams (IIa—d). Photocyclisation of the N-(pyridylcarbonyl)enamines (VIII)–(IX) gave products (X)–(XVI) with incorporation of solvent alcohol.