Predominance of the triketo tautomer in acyldipivaloylmethanes in solution and the solid state.

Highlights: [•] Five 1,3,3′-triketones derived from dipivaloylmethane have been prepared. [•] Both in the solid and in solution no enol tautomers were detected for any of the compounds. [•] Slow isotopic exchange in CD3OD solution indicates presence of a minute amount of the enol. [•] The predominance of the triketo tautomer is attributed to steric hindrance in enol molecules. [ABSTRACT FROM AUTHOR]