A Photo‐Triggered Traceless Staudinger–Bertozzi Ligation Reaction. Issue 33 (7th July 2016) - Hu, Peng
Abstract: The use of light to control the course of a chemical/biochemical reaction is an attractive idea because of its ease of administration with high precision and fine spatial resolution. Staudinger ligation is one of the commonly adopted conjugation processes that involve a spontaneous reaction between azides and arylphosphines to form iminophosphoranes, which further hydrolyze to give stable amides. We designed an anthracenylmethyl diphenylphosphinothioester (1 ) that showed promising Staudinger ligation reactivity upon photo‐excitation. Broadband photolysis at 360–400 nm in aqueous organic solvents induced heterolytic cleavage of its anthracenylmethyl–phosphorus bond, releasing a diphenylphosphinothioester (2 ) as an efficient traceless Staudinger–Bertozzi ligation reagent. The quantum yield of such a photo‐induced heterolytic bond‐cleavage at the optimal wavelength of photolysis (376 nm) at room temperature is ≥0.07. This work demonstrated the feasibility of photocaging arylphosphines to realize the photo‐triggering of the Staudinger ligation reaction. Abstract : Without a trace ! Broadband photolysis at 360–400 nm in aqueous organic solvents induced heterolytic cleavage of the anthracenylmethyl–phosphorus bond of an anthracenylmethyl diphenylphosphinothioester, releasing a diphenylphosphinothioester as an efficient traceless Staudinger–Bertozzi ligation reagent.