Yutilova K. Tetraalkylammonium salts and tertiary amines as nucleophilic catalysts of (chloromethyl)oxirane acetolysis

The thesis is devoted to the research of catalytic acetolysis of (chloromethyl)oxirane under excess of the latter in the binary solvents ECH : tetrahydrofuran and ECH : nitrobenzene. The regioselectivity and kinetic regularities of the reaction depending on the catalyst structure and the solvent polarity under catalysis by tetraalkylammonium halides and tertiary amines were studied. It was shown that the catalytic activity of the latter is determined by their nucleophilicity. It was proved that the first stage of the reaction under catalysis by aliphatic tertiary amines includes their quaternization with the in situ formation of the quaternary ammonium carboxylates. The temperature effect on the reaction kinetics in solvents of different polarity was studied, the enthalpy-entropy compensation effect was established. The reaction products were isolated and characterized. It was shown that the regioselectivity of the reaction rises with the decrease of solvent polarity, increase of nucleophilicity of the halide anion and radii of ions of tetraalkylammonium salts. Quantum chemical modelling of the ring opening of (chloromethyl)oxirane by amines MenEt3–nN, bromides and alkali metal acetates (electrophile-nucleophile) was performed. The mechanism of nucleophilic oxirane ring opening by proton-donating reagents was detailed. The favorable role of electrophilic activation, the optimal directions of stereo- and regio-attack of the nucleophile on ring were established.