Exploring the Dynamics of the Photoinduced Ring-Opening of Heterocyclic Molecules

J Phys Chem Lett. 2017 Jul 20;8(14):3440-3451. doi: 10.1021/acs.jpclett.7b01219. Epub 2017 Jul 12.

Abstract

Excited states formed by electron promotion to an antibonding σ* orbital are now recognized as key to understanding the photofragmentation dynamics of a broad range of heteroatom containing small molecules: alcohols, thiols, amines, and many of their aromatic analogues. Such excited states may be populated by direct photoexcitation, or indirectly by nonadiabatic transfer of population from some other optically excited state (e.g., a ππ* state). This Perspective explores the extent to which the fast-growing literature pertaining to such (n/π)σ*-state mediated bond fissions can inform and enhance our mechanistic understanding of photoinduced ring-opening in heterocyclic molecules.