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Updated: Aug 11, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Disjoint molecular orbitals in nonalternant conjugated diradical hydrocarbons
1Department of Chemistry, University of Missouri, Kansas City, Missouri 64110-2499, USA. diasj@umkc.edu
Abstract:
The concept of disjoint NBMOs in diradical alternant hydrocarbons (AHs) is reviewed and extended to diradical nonalternant hydrocarbons (nonAHs). A valence-bond (VB) method for recognizing disjoint versus nondisjoint NBMOs (nonbonding molecular orbitals) in diradicals is presented. When circumscribed with hexagonal rings, disjoint diradicals produce nonradical polycyclic successors and nondisjoint diradicals produce diradical polycyclic successors. The interconnection between the topological VB terms of cross-conjugated, disjoint NBMOs, and essentially disconnected polycyclic hydrocarbons is delineated.
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