Carbanions, carbenium ions or radicals, formally derived by detachment of one hydron, hydride or hydrogen from the
CH3 group of propene or derivatives thereof. E.g.
H2C=CHCH2+ allyl cation.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1315 (https://doi.org/10.1351/pac199567081307)