New Insights into Bond Homolysis Process and Discovery of Novel Bonding System (C–π–C) by Generating Long-lived Singlet Diradicals

In recent years, low-valent chemical species such as radicals and carbenes, which have been recognized as short-lived intermediates, have been isolated by appropriate molecular design, and their chemical properties have been investigated in detail experimentally. In particular, the discovery of isolable carbenes, which are now widely used as indispensable ligands in coordination chemistry and synthetic organic chemistry, has enabled the development of novel highly active catalysts.