The mol-ecular structure of the title compound, C(8)H(12)N(2)O, indicates that 2-isopropyl-6-methyl-pyrimidin-4-ol (the enol-form) undergoes an enol-to-keto tautomerism during the crystallization process. The pyrimidin-4(3H)-one group is essentially planar, with a maximum deviation of 0.081 (1) Å for the O atom. In the crystal structure, symmetry-related mol-ecules are linked into centrosymmeti...

An efficient semiclassical approach is developed and used to calculate the coherent-control map and time dependent decoherence measure for the excited-state proton transfer dynamics associated with the keto-enolic tautomerization reaction of 2-(2'-hydroxyphenyl)-oxazole. The method extends the usual bichromatic coherent-control scenario to simulate control at finite times after photoexcitation ...

X-ray structural analyses of two a,y-diketo esters and one a,y-diketo acid, which are amino acid antagonists, have shown them all to be present in the solid state in the a,ßunsaturated y-keto enolic form. The structures of the esters /3-acetyl-pyruvic acid methyl ester (1) and 2-oxo-cyclopentyl-glyoxylic acid ethyl ester (3) are stabilized by intramolecular O---H(-O) hydrogen bonds involving th...

This article presents a study of the excited state relaxation dynamics N-salycylidene-o-aminophenol (SOAP) in ethanol solution. Femtosecond transient absorption (TA) spectroscopy and theoretical calculations are used combination to establish mechanism type molecular species involved accompanying phototransformations. TA spectra show that upon photoexcitation two SOAP tautomers (E-enol Z-keto) i...

Abstract The keto‐switched photocatalysis of covalent organic frameworks (COFs) for efficient H 2 evolution was reported the first time by engineering, at a molecular level, local structure and component skeletal building blocks. A series imine‐linked BT‐COFs were synthesized Schiff‐base reaction 1, 3, 5‐benzenetrialdehyde with diamines to demonstrate structural reconstruction enol keto configu...

An isopyrazole (4H-pyrazole)-embedded nonane-2,4,6,8-tetraone derivative was synthesized as a masked-tetraketone for stepwise and multiple functionalization. The has six possible tautomers, but exists predominantly 12π-electron conjugated keto-enamine-imine-enol form, which also observed in the solid state by single crystal X-ray analysis. Stepwise functionalization to introduce metal-coordinat...

New DKR type: An N-heterocyclic carbene (NHC)-catalyzed dynamic kinetic resolution of racemic α-substituted β-keto esters has been developed. This method relies on the epimerization of an NHC-enol intermediate before subsequent aldol/acylation events. Highly substituted β-lactones are produced in good yield with good to excellent selectivities (see scheme).

Studies with deuterium as a tracer have shown that wheat germ and pig heart malic dehydrogenase act on the keto form of oxaloacetic acid (1, 2). The keto form of this acid has also been shown to arise in the enzymatic carboxylation of phosphorylenolpyruvate by wheat germ phosphoryl-enolpyruvate carboxylase (3) and by avian liver phosphoryl-enolpyruvate carboxylase kinase (2). In an attempt to e...