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Updated: Sep 28, 2025
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Photoinduced Hydrophosphination of Terminal Alkynes with Tri(o-tolyl)phosphine: Synthesis of Alkenylphosphonium Salts
Daichi Ikeshita1, Yusuke Masuda1, Naoki Ishida1
1Department of Synthetic Chemistry and Biological Chemistry, Kyoto University, Katsura, Kyoto 615-8510, Japan.
Abstract:
Herein reported is a photoinduced hydrophosphination reaction of terminal alkynes with tri(o-tolyl)phosphine to form alkenylphosphonium salts. The reaction is more sustainable than conventional methods since it dispenses with the need for elaborated starting materials and precious transition metals. The o-methyl groups of tri(o-tolyl)phosphine play two important roles: (1) to guide the phosphorus radical to add onto the terminal sp carbon and (2) to donate a hydrogen atom onto the developing sp2 carbon radical intramolecularly.
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