Solvent effects on the kinetics of the reaction between diphenylcarbonyl oxide and olefins

The k(11) rate constants for the reaction between diphenylcarbonyl oxide an d seven olefins were determined by the method of pulsed photolysis. The k(1 1) values depend on the natures of olt fns and solvents and change from 11 +/- 3 for styrene in acetonitrile to (6.0 +/- 0.6) x 10(4) dm(3) mol(-1) s( -1) for 1,4-dichlorobutene-2 in n-decane. The rate constants for symmetrica l olefins such as I,4-dichlorobutene-2, stylbene, and cis-1,2-dichloroethyl ene are 1-2 orders of magnitude larger than for styrene, hexene-1, n-butyl vinyl ether, and 2-bromopropene-1. Solvent effects on k(11) are considered in terms of the Winstein-Grunwald equation. An increase in solvent polarity stabilizes carbonyl oxide and decreases the rate constant for the reaction . The products formed in the reaction between Ph2COO and styrene were studi ed. A possible mechanism of the reaction is discussed.