Rotamer-Controlled Dual Emissive α-Amino Acids

Abstract

The synthesis and photoluminescent properties of novel α-amino acids are described in which the biaryl benzotriazinonecontaining chromophores were found to display dual emission fluorescence via locally excited (LE) and twisted intramolecular charge transfer (TICT) states. The intensity of each emission band could be controlled by the electronics and position of the substituents, and this led to the design of a 2-methoxyphenyl analogue that, due to twisting, displayed bright TICT fluorescence, solvatochromism, and pH sensitivity.

Synthesis of Thiazoloindole α-Amino Acids: Chromophores Amenable to One- and Two-Photon Induced Fluorescence

“…A range of electron-rich and electron-deficient arene substituents were then incorporated via a Suzuki–Miyaura reaction . The use of the Buchwald XPhos Pd G2 catalyst allowed efficient cross-coupling reactions (74–88% yields), under relatively mild conditions and fast reaction times. , Overall, this four-step route allowed efficient access to a small library of novel α-amino acids with the late-stage incorporation of diversity.…”