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Updated: Jul 2, 2025
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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
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Radical revelations: the pnictogen effect in linear acetylenes
Miguel Gallegos1, Vicente Del Amo2, José Manuel Guevara-Vela3
1Departamento de Química Física y Analítica, Universidad de Oviedo, Oviedo E-33006, Spain. ampendas@uniovi.es.
Physical Chemistry Chemical Physics : PCCP
|February 19, 2024
Summary
Dipnictogenoacetylenes (DXAs) exhibit unique chemistry influenced by the pnictogen (X) element. Theoretical studies reveal that second-period elements differ significantly, leading to zwitterionic forms and potential free-radical chemistry pathways.
Area of Science:
- Organic Chemistry
- Theoretical Chemistry
- Inorganic Chemistry
Background:
- Acetylenes are versatile building blocks in chemical synthesis.
- Introducing heteroatoms, specifically pnictogens (X), modifies the acetylene triple bond.
- Dipnictogenoacetylenes (DXAs) display varied chemical properties contingent on the pnictogen element.
Purpose of the Study:
- To investigate the origin of chemical differences in dipnictogenoacetylenes (DXAs).
- To evaluate the impact of pnictogen (X) identity on DXA geometry and electronic structure.
- To analyze the carbene character and isomer interconversion mechanisms in DXAs.
Main Methods:
- Utilizing rigorous theoretical chemistry computational tools.
- Performing detailed evaluations of geometrical and electronic features.
- Analyzing the interconversion mechanism between linear and zigzag isomers.
Main Results:
- Second-period pnictogens exhibit distinct behavior compared to heavier congeners.
- A zwitterionic resonance form emerges down the pnictogen group, reducing carbenoid character.
- Electrostatically driven ring closure is observed for heavier pnictogens.
Conclusions:
- The nature of the pnictogen (X) critically dictates DXA properties and reactivity.
- Findings suggest potential for novel free-radical chemistry promotion.
- Theoretical insights elucidate structure-property relationships in DXAs.
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