Synthesis and second-harmonic generation properties of 2-(4-nitroanilino)-1,3,5-triazine derivatives

Abstract

The synthesis and non-linear optical properties of a series of 2-(4-nitroanilino)-1,3,5-triazine compounds are described. The triazines show various activities in powder second-harmonic generation (SHG) depending on the structures and have absorption maxima at ⩽350 nm, shorter by 30–50 nm than those of the parent nitroanilines. 2-(4-Nitroanilino)-4,6-diphenyl-1,3,5-triazine affords different crystalline materials depending on the recrystallization solvent. A crystal formed by recrystallization from toluene reveals a high powder SHG activity comparable with that of 2-methyl-4-nitroaniline, while recrystallization from N,N-dimethylformamide gives an SHG-inactive crystal in which solvent molecules are incorporated in a 1:1 ratio by hydrogen bonding. The crystal structure of the latter was determined.