This prefix is now rejected. It has been used in the past, especially in cyclic systems, to name @C00806@, e.g. 'carbenacycloheptane', now cycloheptylidene.
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]
Citation: 'carbena' in IUPAC Compendium of Chemical Terminology, 3rd ed. International Union of Pure and Applied Chemistry; 2006. Online version 3.0.1, 2019. https://doi.org/10.1351/goldbook.C00805 RISBibTexEndNote