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Updated: May 29, 2025

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最近在4CzIPN介导的功能化与基前体的进展:单双光催化系统和双光催化系统

Ajay Uppuluru1, Pratheepkumar Annamalai1, Kishor Padala2

  • 1Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Katpadi, Vellore, Tamil Nadu, 632014, India. pratheepkumar.a@vit.ac.in.

Chemical communications (Cambridge, England)
|February 6, 2025
PubMed
概括

1,2,3,5-tetrakis ((carbazole-9-yl)-4,6-dicyanobenzene) (4CzIPN) 是一种无金属的光催化剂,可以推动可持续的有机合成. 在温和的条件下,它能够有效地形成C-C和C-X键,脱碳化,化和循环化反应.

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Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
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The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
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