Year: 2026
Type: article
Abstract: Alkenes typically have trigonal planar geometries at each terminus, with favourable σ- and π-bonding leading to a bond order of ~2. Here we consider unusual alkenes that possess an extreme form of geometric distortion, termed hyperpyramidalization. In a hyperpyramidalized alkene, geometries deviate remarkably from the typical trigonal planar alkene geometry, leading to weak π-bonding and abnormal alkene bond orders approaching 1.5. Cubene and 1,7-quadricyclene, first validated in 1988 and 1979, respectively, but overlooked for decades since, are the focus of the present study. We leverage their unusually weak π-bonds in cycloadditions, enabling the construction of complex scaffolds and access to previously unrealized chemical space. The origins of the unusually low bond orders were investigated using computational methods. These efforts are expected to prompt future studies of molecules that display hyperpyramidalization or atypical bond orders.
Source: Nature Chemistry
Institution: University of California, Los Angeles
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $12,690
Funders: National Science Foundation, U.S. Department of Energy, National Institutes of Health, National Institute of General Medical Sciences, National Center for Research Resources, Division of Chemistry, Office of Research Infrastructure Programs, National Institutes of Health, Institute for Digital Research and Education, University of California, Los Angeles
Awards: G1017409961, Acquisition of Upgraded NMR Instrumentation for Chemistry Research, Education and Training, G1565084568, G1661892572, G1695705655, G1751077203, G1752470959, G2607749399, G310123084, G3295719173, NMR Console and Prodigy CryoProbe, G401885085, G6121853222, XSEDE: eXtreme Science and Engineering Discovery Environment, Experimental and Theoretical Investigations of Organic Reaction Rates and Mechanisms, G7435049567, G7579982596, UCLA-DOE INSTITUTE FOR GENOMICS AND PROTEOMICS, G863947390, G895126265, CENTER FOR GENOMICS AND PROTEOMICS RESEARCH PROGRAM, G910930967
OpenAlex ID: W7125219819