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Core-extended terrylene diimide on the bay region: synthesis and optical and electrochemical properties

Qianqian Bai1, Baoxiang Gao, Qi Ai

  • 1College of Chemistry and Environmental Science, Hebei University, Baoding, 071002, P. R. China.

Organic Letters
|November 23, 2011
PubMed

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Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
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The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
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