SOMO-HOMO Conversion in Triplet Carbenes

Org Lett. 2021 Jul 2;23(13):4955-4959. doi: 10.1021/acs.orglett.1c01137. Epub 2021 May 28.

Abstract

In this study, the SOMO-HOMO conversion has been shown for the first time in triplet carbenes embedded in cycloparaphenylene units. The high-lying HOMO originating from the curved π-conjugated system and the low-lying SOMO-1 originating due to the small carbene angle are the key to endowing this interesting electronic configuration. Furthermore, simple planar triplet carbenes such as fluorenylidene were found to possess SOMO-HOMO energy-converted electronic configurations.