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Updated: May 10, 2025

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes

Published on: September 8, 2013

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酸:一种可见光驱动的无痕辅助剂,用于立体选择性环基结构

Subhashis Mondal1, Shyamal Pramanik1, Soumitra Maity1

  • 1Department of Chemistry and Chemical Biology, Indian Institute of Technology (ISM), Dhanbad, Jharkhand 826004, India. smaity@iitism.ac.in.

Chemical communications (Cambridge, England)
|April 22, 2025
PubMed
概括

这项研究介绍了一种简单的方法,用于从基因中制造环基,使用无痕酸辅助剂. 这种方法克服了化物中间体的问题,使得在循环化反应中可以使用激素前体.

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Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is 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.
Selection Rules: Photochemical Activation
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