Open AccessObservations and comments on the mechanism of epoxidation of alkenes by manganese(III) porphyrins with hypochlorite.
Author(s) -
William R. Lee,
Paul C. Nakagaki,
Balasubramanian Palaniappan,
Thomas C. Bruice
Publication year - 1988
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.85.3.641
Subject(s) - manganese , porphyrin , chemistry , hypochlorite , photochemistry , inorganic chemistry , olefin fiber , hypervalent molecule , catalysis , reagent , reaction rate constant , organic chemistry , kinetics , physics , quantum mechanics
The kinetics of olefin epoxidation in a methylene chloride/water biphase containing a phase-transfer agent with hypochlorite as oxygen transfer reagent and manganese(III) tetraphenylporphyrin catalysts has been reinvestigated. The results do not support the accumulation of an intermediate composed of an alkene and a hypervalent metaloxo porphyrin. Second-order rate constants for oxygen transfer from hypochlorite to the manganese porphyrin, comproprotionation of the hypervalent manganese-oxo porphyrin with manganese(III) porphyrin, and olefin epoxidation by the hypervalent manganese-oxo porphyrin were obtained from experiments in a wet organic monophase.