Picosecond kinetics by exchange broadening in the infrared and Raman. 2. Acetylacetone

Spectra of acetylacetone, CH₃COCH₂COCH₃, and its partially deuterated analogue, CH₃COCD₂COCH₃, in the region of the C=O and C=C stretches were taken over a wide temperature range. The results could be interpreted on the assumption that the cis enolic modification of acetylacetone exists in two different, rapidly interconverting forms. The kinetics of the interconversion, in the picosecond range, were investigated and rate constants and energies and entropies of activation determined. The nature of the two forms of the cis enol is discussed.