Mechanism of the catalytic decomposition of cumyl hydroperoxide inhibited by 2-methylpropanol-1

The kinetics of cumyl hydroperoxide (CHP) decomposition catalyzed by molybdenyl propanediolate (Cat) and decomposition products are studied in the presence of 2-methylpropanol-1 (MP). Phenol, acetone, 2-phenylpropanol-2 (PhP), and acetophenone (APh) are the main products of cumyl hydroperoxide decomposition. The concentration of 2-methylpropanol-1 affects not only the ratio between the rates of heterolytic and homolytic decomposition of cumyl hydroperoxide, but also the ratio between the products of hydroperoxide homolysis, that is, the [2-phenylpropanol-2]/[acetophenone] ratio. The dissociation constants calculated for the catalyst-2-methylpropanol-1 and catalyst-2(2-methylpropanol-1) complexes are 0.275 and 4.910 mol/l, respectively. The exchange of hydroperoxide ligands in the ROH-catalyst-ROOH systems was studied by 1 H NMR spectroscopy. Exchange interactions affect the rate and direction of hydroperoxide decomposition.