Diastereoselective intramolecular [4 + 4] photocycloaddition reaction of N-(naphthylcarbonyl)anthracene-9-carboxamides: temperature effects and reversal of diastereoselectivity
Diastereoselective intramolecular [4 + 4] photocycloaddition reaction of N-(naphthylcarbonyl)anthracene-9-carboxamides: temperature effects and reversal of diastereoselectivity
Conformation of aromatic foldamers possessing three aromatic rings in a sequence of anthracene - phenylene - anthracene linked with iminodicarbonyl was examined. Their folding structures were confirmed by single crystal X-ray analysis. Two conformations, straight-zigzag and helically-zigzag conformations, were found depending on the substituents at the imide nitrogen atom. Induced circular dichroism originated in the interaction of the upper and bottom anthracene moieties was observed both in solution and in the solid state. (c) 2007 Elsevier Ltd. All rights reserved.