Heteroaromatic Cation-Based Chromophores: Synthesis and Nonlinear Optical Properties of Alkynylazinium Salts
Heterocycles; Cations; Chromophores; Synthesis; Nonlinear optics
Abstract A variety of alkynylazinium cationic (D-π-A%@2B) chromophores were prepared in good yields by the reaction of bromoazinium (pyridinium, quinolinium, and isoquinolinium iodides) with alkynes under Sonogashira conditions. The analysis of the experimentally recorded spectra is supported by quantum chemical calculations using restricted configuration interaction and density functional methods. First-order hyperpolarizabilities of (D-π-A%@2B) azinium-based cations as a new class of second-order nonlinear optical (NLO) chromophores were also studied by hyper-Rayleigh scattering experiments and computational procedures.