title: A Photo-Triggered Traceless Staudinger-Bertozzi Ligation Reaction.
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.
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Hu
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.|Advanced Laboratory for Environmental Research & Technology, USTC-CityU, Suzhou, China.|CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
authors.forename: Tianshi
authors.initials: T
authors.lastname: Feng
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Chi-Chung
authors.initials: CC
authors.lastname: Yeung
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Chi-Kin
authors.initials: CK
authors.lastname: Koo
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Kai-Chung
authors.initials: KC
authors.lastname: Lau
authors.affiliation: Department of Chemistry and Biology, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR, China. bhmhwlam@cityu.edu.hk.
authors.forename: Michael H W
authors.initials: MH
authors.lastname: Lam
keywords: Staudinger-Bertozzi ligation; conjugation reaction; phosphonium salt; photo-triggering; photolysis