pseudo acids

https://doi.org/10.1351/goldbook.P04920
Potentially acidic compounds that require some structural reorganization, such as @K03382@–enol @T06253@, having a non-negligible @A00093@ energy, in order to show normal acidic properties, e.g. nitroalkanes:
P04920.png
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1361 [Terms] [Paper]