Photoinduced Dearomatizing Three‐Component Coupling of Arylphosphines, Alkenes, and Water

Abstract

A unique photoinduced reaction that couples a triarylphosphine, an alkene, and water to produce 2‐(cyclohexa‐2,5‐dienyl)ethylphosphine oxide is reported herein. The alkene inserts into a C(aryl)−P bond of the arylphosphine, the aryl ring is dearomatized into the cyclohexadienyl ring, and the phosphorus is oxidized. The three components are all readily available, and their intermolecular coupling significantly increases molecular complexity. The products formed are applicable to the Wittig olefination.

Organophosphine as an Alkyl Transfer Shuttle for the Direct β-Alkylation of Chalcones Using Alkyl Halides

“…On the basis of the experimental results, a tentative mechanism was proposed to rationalize the reaction pathway. As shown in Scheme 7, the reactions started with the formation of quaternary phosphonium salts A from 1 and 9 a P�O bond was formed with the removal of an alkyl group. This accomplished the β-alkylation of the chalcones using phosphonium salts as alkyl transfer reagents.…”

A green approach for the synthesis of π conjugated phosphonium salts under visible-light irradiation using air as oxidant

“…Murakami's group has successively used this approach to develop reactions of triarylphosphine with substituted alkenes or alkynes to produce new phosphine oxides, tricyclic phosphonium salts, cyclopentane phosphonium salts and alkenyl phosphonium salts. [6] Abigail G. Doyle and Zhao groups have also achieved the generation of nitrogen free radicals by using the reaction of triarylphosphine, sulfonamide and hydroxylamine, respectively. [7] In 2022, Dilman's research group reported the use of triphenylphosphonium triflate as a key intermediate in the hydrophosphorylation of unactivated alkenes, with the producing phosphonium being directly used in the Wittig reaction.…”