A new class of N-H proton transfer molecules

Facile derivation of 10-aminobenzo[h]quinoline via replacing one of the N-H hydrogen atoms by various substituents generates a new series of excited-state intramolecular N-H proton-transfer molecules, for which the proton-transfer emission can be widely tuned from 590 nm to 770 nm simply by harnessing the electron-donating/withdrawing strength of the substituents.