Palladium (II) coordination complexes catalyze the reaction of alcohols with ketones to yield ethers. During the catalytic cycle, the alcohol adds selectively to the β-carbon (anti-Markovnikov). In this work, mechanism and kinetics for the reaction of methanol with methyl vinyl ketone (MVK), being catalyzed by Pd, has been theoretically investigated in detail. Using quantum mechanical approach,...

The effect of Ni(II), Cu(II) and Zn(II) association on the diketo/keto-enol tautomerism of thymine has been investigated through the use of B3LYP density functional theory calculations. Final energies were obtained at the B3LYP/6-311+G(2df,2p)//B3LYP/6-311+G(d,p) level of theory. Ni(II) and Cu(II) lead to an oxidation of thymine which for Zn(ii) is only partial and catalyze the tautomerization ...

The dialkyl 2,6-dialkylsubstituted 4-piperidone-3,5-dicarboxylates were synthesized by a Mannich procedure. Depending on the substitution at the nitrogen keto-enol-tautomerism and a configurational isomerism at C 2 is observed. The structure o f the N-substituted piperidone 24 E (C 18H29N 0 5) has been determined by X-ray analysis: it is characterized by an enol structure o f the /?-ketoester a...

Curcumin, derived from Curcuma longa plant has been shown to exhibit antioxidant, antiinflammatory, antiviral, antibacterial, antifungal, and anticancer activities and thus has a potential against various malignant diseases, diabetes, allergies, arthritis, Alzheimer’s disease, and other chronic illnesses [1–3]. In the light of these promising propertiesseveral questions need to be answered in o...

palladium (ii) coordination complexes catalyze the reaction of alcohols with ketones to yield ethers. during the catalytic cycle, the alcohol adds selectively to the β-carbon (anti-markovnikov). in this work, mechanism and kinetics for the reaction of methanol with methyl vinyl ketone (mvk), being catalyzed by pd, has been theoretically investigated in detail. using quantum mechanical approach,...

The present paper describes a new enzyme from animal tissues which catalyzes the keto-enol tautomeriaation of the phenylpyruvic acids. Preliminary accounts of this tautomerase have been published (1, 2). The enzyme has not yet proved to be essential in any biological reaction, but a physiological role may be expected since specific tautomers of a-keto acids are substrates or products in some re...