Related Experiment Video
Updated: May 9, 2026

Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of Phosphorus(I)
Published on: November 22, 2016
Homolytic substitution at phosphorus for C-P bond formation in organic synthesis
1Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan ; ACT-C, Japan Science and Technology Agency, Sakyo-ku, Kyoto 606-8502, Japan.
Abstract:
Organophosphorus compounds are important in organic chemistry. This review article covers emerging, powerful synthetic approaches to organophosphorus compounds by homolytic substitution at phosphorus with a carbon-centered radical. Phosphination reagents include diphosphines, chalcogenophosphines and stannylphosphines, which bear a weak P-heteroatom bond for homolysis. This article deals with two transformations, radical phosphination by addition across unsaturated C-C bonds and substitution of organic halides.
Related Concept Videos
Aldehydes and Ketones to Alkenes: Wittig Reaction Mechanism
The reaction begins with the nucleophilic addition between a phosphorus ylide and the carbonyl compound. Due to its carbanionic character, phosphorus ylide acts as a strong nucleophile and attacks the electrophilic carbonyl group. This generates a charge-separated dipolar intermediate called betaine. The negatively charged oxygen atom and...
Nucleophilic Substitution Reactions
In 1896, the German chemist Paul Walden discovered that he could interconvert pure enantiomeric (+) and (-) malic acids through a series of reactions. This conversion suggested the involvement of optical inversion during the substitution reaction. Further, in 1930, Sir Christopher Ingold described for the first time two different forms of nucleophilic substitution reactions, which are known as SN1 (nucleophilic substitution unimolecular) and SN2 (nucleophilic substitution...
Acid Halides to Carboxylic Acids: Hydrolysis
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...
α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction
Carboxylic Acids to Acid Chlorides
Aldehydes and Ketones to Alkenes: Wittig Reaction Overview
