An improved procedure has been developed for photodehydrocyclization of stilbenes for the synthesis of phenanthrenes and helicenes. This procedure involves the use of THF as a scavenger of hydriodic acid produced during iodine mediated photodehydrocyclization. The use of THF is advantageous due to its higher boiling point, lower cost and easy availability as compared to propylene oxide. The method is applied to synthesize a number of phenanthrenes and helicenes.

Air stable and easily accessible, 1-(a-aminobenzyl)-2-naphthols are used as efficient phosphine-free ligands in palladiumcatalyzed Suzuki reaction for a variety of substrates under conventional heating as well as ultrasonic conditions. Multibrominated aromatic substrates were successfully converted to corresponding arylated moieties with good conversion and selectivity. A novel one-pot two-step cascade reaction strategy involving Wittig and Suzuki reactions is developed for efficient synthesis of 4-styryl biphenyls (C 6 -C 2 -C 6 -C 6 unit).

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