1. A study of solvent effect on photochemically induced reations between pyridinedicarbonitriles and alkenes: an easy approach to the synthesis of cyclopenta [b or c]pyridines Rosanna Bernardi,Tullio Caronna,Daniela dal Pio Luogo,Sergio Morrocchi,Gabriella Poggi,Bruno M. Vittimberga J. Chem. Soc. Perkin Trans. 1 1996 1593