10.1134/S0036024407010050
The study investigates the kinetics and mechanism of the alcoholysis of symmetrical dioctylurea in inert solvents, with n-octanol as the alcohol involved. The reaction follows two parallel pathways: one involving the dissociation of initial urea and the other, bimolecular interaction. The researchers used various solvents, including decane, phenetole, o-dichlorobenzene, benzonitrile, and nitrobenzene, to study the influence of solvent properties on the reaction rate. The reaction products were analyzed using proton NMR spectroscopy and photocolorimetry. The study found that the specific rate of the alcoholysis of N,N'-dioctylurea linearly depended on the initial concentration of octanol, indicating that the reaction proceeds via both dissociative and associative routes. The rate constants for these processes were determined and correlated with solvent properties using the Palm–Koppel equation.
10.1021/acs.orglett.0c02635
The study presents the development of a catalytic system for the C-alkylation of N-heterocyclic compounds, such as pyridine, pyrimidine, pyrazine, quinoline, quinoxaline, and isoquinoline, using alcohols. The process is based on a hydrogen-borrowing approach and utilizes [Cp*IrCl2]2 as the catalyst precursor, combined with potassium t-butoxide and 18-crown-6-ether. This method is environmentally friendly as it only produces water as a byproduct. The researchers optimized the reaction conditions and demonstrated the system's versatility by applying it to various substrates, achieving good to excellent yields. The study also proposed a possible reaction mechanism involving three steps: hydrogen transfer from alcohol to iridium catalyst, cross-aldol-type condensation, and transfer hydrogenation. The developed catalytic system is expected to contribute to the synthesis of pharmaceuticals and functional materials.
Xi
Xi:Irritant;
