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Site-Selective Sequential Isocyanide Insertion at Dual sp3- and sp2-Carbon Centers Enables Divergent Access to

Zhi-Lin Ren1,2, Ke-Ji Li1, Cheng-Cheng Ding3

  • 1College of Chemical Engineering, Hubei University of Arts and Science, Xiangyang, Hubei441053, China.

Organic Letters
|September 2, 2026
PubMed

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Cycloadditions are one of the most valuable and effective synthesis routes to form cyclic compounds. These are concerted pericyclic reactions between two unsaturated compounds resulting in a cyclic product with two new σ bonds formed at the expense of π bonds. The [4 + 2] cycloaddition, known as the Diels–Alder reaction, is the most common. The other example is a [2 + 2] cycloaddition.
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