meso-Methyl Amination of BODIPYs by Regiospecific Cross Dehydrogenative Coupling via Direct C(sp³)–N(sp³) Bond Formation

Abstract

Herein, we report a direct meso-methyl amination of BODIPY dyes by C(sp 3 )−N(sp 3 ) bond formation using PIDA as an oxidant with a wide range of aliphatic secondary amines. This metal free cross dehydrogenative coupling reaction is regiospecific at the meso-methyl position of BODIPY in the presence of C1, C3, C5, and C7 methyl groups. Detailed nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and X-ray crystallographic studies were performed to establish the reaction mechanism and the regiospecificity of the reaction. Finally, the photophysical and electrochemical properties of the newly synthesized dyes were evaluated and rationalized.