Rotamer-Controlled Dual Emissive & alpha;-Amino Acids

The synthesis and photoluminescent properties of novel & alpha;-aminoacids are described in which the biaryl benzotriazinone-containingchromophores were found to display dual emission fluorescence vialocally excited (LE) and twisted intramolecular charge transfer (TICT)states. The intensity of each emission band could be controlled bythe electronics and position of the substituents, and this led tothe design of a 2-methoxyphenyl analogue that, due to twisting, displayedbright TICT fluorescence, solvatochromism, and pH sensitivity.