Salts of
enols (or of the tautomeric
aldehydes or
ketones ), in which the anionic charge is delocalized over oxygen and carbon, or similar
covalent metal derivatives in which the metal is bound to oxygen.
Source:
PAC, 1995, 67, 1307
(Glossary of class names of organic compounds and reactivity intermediates based on
structure (IUPAC Recommendations 1995))
on page 1334