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Title: Kinetics and mechanism of the epoxidation of allylic alcohols by hydrogen peroxide with methyltrioxorhenium as catalyst

The title reaction was carried out in aqueous acetonitrile (5% and 20% water) and in nitromethane. Provided acid was not added, the product was mostly the epoxide, accompanied by small amounts of the triol that results from acid-catalyzed ring opening of the epoxide. With added acid, only the triol was detected. The kinetic study afforded a striking result: only the diperoxorhenium compound was an epoxidation catalyst; the monoperoxo compound CH{sub 3}Re(O){sub 2}({eta}{sup 2}-O{sub 2}) was inactive; no other substrates, including nonallylic alkenes, show that reactivity difference. This, together with the realization of high diastereoselectivity for 2-cyclohexen-1-ol in chloroform, suggests a particular mode of hydrogen bonding: an O atom of one peroxo group engages in oxygen transfer, in a transition state that is stabilized by hydrogen bonding between the allylic OH group and O atom of the other peroxo group. Calculations supported that conclusion.
Authors:
;  [1]
  1. Ames Lab., IA (United States)|[Iowa State Univ., Ames, IA (United States). Dept. of Chemistry
Publication Date:
OSTI Identifier:
346926
Resource Type:
Journal Article
Resource Relation:
Journal Name: Inorganic Chemistry; Journal Volume: 38; Journal Issue: 5; Other Information: PBD: 8 Mar 1999
Country of Publication:
United States
Language:
English
Subject:
40 CHEMISTRY; ALCOHOLS; OXIDATION; EPOXIDES; HYDROGEN PEROXIDE; RHENIUM COMPOUNDS; CATALYTIC EFFECTS; CHEMICAL REACTION KINETICS