carbene radical anions

https://doi.org/10.1351/goldbook.C00809
Species R2C, having three non-bonding electrons, formally derived by addition of an electron to a @C00806@.
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1324 [Terms] [Paper]