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Updated: Nov 2, 2025
Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
A Primary Acyl Phosphine Stabilized by a Phosphonium Ylide
David A Petrone1, Kevin M Szkop1, Linkun Miao1
1Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario, M5S3H6, Canada.
Abstract:
Primary acyl-phosphines are scarce in the literature. Here we show that the reaction of Ph3 GePCO with the ylide Ph3 PCH2 proceeds to give the species Ph3 PCHC(O)PH(GePh3 ) 1. Deprotonation of 1 with Na[N(SiMe3 )2 ] generates the salt [Na(THF)2 ][Ph3 PCHC(O)P(GePh3 )] 2 which provides subsequent access to the bis-germanylated acylphosphine, Ph3 PCHC(O)P(GePh3 )2 3. Alternatively, treatment of 1 with HCl in dioxane affords the primary acylphosphine Ph3 PCHC(O)PH2 4. Compound 4 is a rare example of an air stable primary acyl-phosphines and the first devoid of a stabilizing heteroatom adjacent to the carbonyl fragment.
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