3-Bromo-2-Pyrone: An Alternative and Convenient Route to Functionalized Phosphinines
Marija H Habicht1, Friedrich Wossidlo1, Manuela Weber1
1Institute of Chemistry and Biochemistry, Freie Universität Berlin, Fabeckstrasse 34/36, Berlin, Germany.
Abstract:
The facile access to 3-bromo-2-pyrone allows the preparation of 6-bromo-2-trimethylsilyl-phosphinine by a [4+2] cycloaddition with Me3 Si-C≡P for the first time. The regioselectivity of this reaction could be verified by means of single crystal X-ray diffraction of the corresponding W(0) complex. In the presence of ZnBr2 and dppp (1,3-bis(diphenylphosphino)propane) as a bidentate ligand, the bromo-phosphinine quantitatively undergoes a Negishi cross-coupling reaction with PhLi that selectively leads to 6-phenyl-2-trimethylsilyl-phosphinine. This heterocycle could again be characterized by means of X-ray diffraction as a W(0) complex. These results describe a new and convenient route to 2,6-disubstituted phosphinines that makes use of readily available starting materials.
More Related Videos
14:11Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
08:46Preparation and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of PhosphorusI
Published on: November 22, 2016
Related Concept Videos
α-Bromination of Carboxylic Acids: Hell–Volhard–Zelinski Reaction
Preparation of 1° Amines: Gabriel Synthesis
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Preparation of Nitriles
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Radical Substitution: Allylic Bromination
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...
