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Updated: Jul 17, 2026
09:58
Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Cyano-stabilized triphenylphosphonium ylids.
Fernando Castañeda1, Clifford A Bunton, Ricardo Baggio
1Departamento de Química Orgánica y Fisicoquímica, Facultad de Ciencias, Químicas y Farmacéuticas, Universidad de Chile, Casilla 233, Santiago, Chile. fcastane@ciq.uchile.cl
Summary
This study reveals that crystalline cyano-stabilized triphenylphosphonium ylids with carbonyl groups exhibit extended electronic delocalization. Intramolecular interactions influence their preferred coplanar conformation in crystal structures.
Area of Science:
- Organic Chemistry
- Crystallography
- Computational Chemistry
Background:
- Triphenylphosphonium ylids are versatile synthetic intermediates.
- Cyano and carbonyl groups can significantly influence electronic properties.
Purpose of the Study:
- To investigate the structural and electronic properties of crystalline cyano-stabilized triphenylphosphonium ylids.
- To understand the role of intramolecular interactions in determining molecular conformation.
Main Methods:
- X-ray crystallography to determine molecular structures.
- Analysis of bond lengths, angles, and torsion angles.
- Examination of intermolecular and intramolecular interactions.
Main Results:
- Extended electronic delocalization was observed in compounds with cyano and carbonyl groups.
- Carbonyl groups were oriented towards the phosphonium cation.
- Intramolecular interactions between carbonyl oxygen and the phosphorus atom were identified as dominant.
- A preferred coplanar conformation was consistent with these interactions.
Conclusions:
- Cyano-stabilized triphenylphosphonium ylids with carbonyl functionalities exhibit significant electronic delocalization.
- Intramolecular interactions play a crucial role in dictating the preferred coplanar conformation of these molecules in the solid state.
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