Novel hydroperoxysultam, 2-(6-bromo-pyrid-2-yl)-2,3,4,5,6,7-hexahydro-1,2-benzisothiazol-3-hydroperoxy 1,1-dioxide: synthesis, crystal structure and kinetics of catalytic interaction with cyclooctene

Abstract

The novel hydroperoxy sultam, 2-(6-bromo-pyrid-2-yl)-2,3,4,5,6,7-hexahydro-1,2-benzisothiazol-3-hydroperoxy 1,1-dioxide (HPS), was synthesized by the oxidation of the isothiazolium salt with hydrogen peroxide. As established by X-ray crystallography the unit cell of HPS in crystal state includes four molecules with a dimeric structure as a result of strong intermolecular hydrogen bond formation. The hydroperoxy sultam interacts with cyclooctene in the presence of molybdenum boride MoB as epoxidation catalyst at 40 °C. The additional consumption of HPS upon catalyst activation leads to an increase in the 1,2-epoxycyclooctane formation selectivity with increasing of HPS concentration. On the basis of the obtained results a kinetic reaction scheme was proposed. The equation for the reaction rate as well as the equation that connects the current concentration of hydroperoxide with reaction time and allows the calculation of the theoretical kinetic curves for HPS consumption were derived according to the kinetic scheme.