β-Thiophene-Fused BF2-Azadipyrromethenes as Near-Infrared Dyes

A facile synthetic route to a new class of near-IR beta-thiophene-fused BF2-azadipyrromethenes (aza-BDTPs) is presented. Sharp absorption and fluorescence emission bands at around 800 nm were observed for these highly photostable aza-BDTPs, with a large absorption coefficient and very low absorptions in the visible range from 700 to 380 nm.