Mechanistic studies of alkene epoxidation catalyzed by nickel(II) cyclam complexes. /sup 18/O labeling and substituent effects
Journal Article
·
· J. Am. Chem. Soc.; (United States)
The oxidations of cyclohexene and various aryl-substituted alkenes are catalyzed by the cyclam (1,4,8,11-tetraazacyclotetradecane) complex of Ni(NO/sub 3/)/sub 2/ with iodosylbenzene as terminal oxidant. Epoxides are the major products; however, small amounts of ring-opened products, over-oxidation to ketones or aldehydes, and allylic oxidation of cyclohexene are also observed. E olefins are more reactive than the corresponding Z olefins in contrast to the results of iron porphyrin catalysis, and kinetic studies of para-substituted styrenes indicate that the reaction is facilitated by electron-donating substituents. Labeling studies with PhI/sup 18/O confirm that the epoxide oxygen is derived from PhIO while allylic oxidation and over-oxidation products involve both PhIO and exogenous sources of oxygen. A pericyclic mechanism for the formation of PhCHO is proposed along with the intermediacy of a high-valent nickel-oxo complex as the active oxidant. These results are discussed in light related transition-metal/PhIO oxidation mechanisms.
- Research Organization:
- State Univ. of New York, Stony Brook (USA)
- OSTI ID:
- 6048347
- Journal Information:
- J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 110:18; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Alkene epoxidations catalyzed by iron(III), manganese(III), and chromium(III) porphyrins. Effects of metal and porphyrin substituents on selectivity and regiochemistry of epoxidation
Mn(III)-Iodosylarene Porphyrins as an Active Oxidant in Oxidation Reactions: Synthesis, Characterization, and Reactivity Studies
Nickel catalysis of olefin epoxidation
Journal Article
·
Wed Sep 13 00:00:00 EDT 1989
· Journal of the American Chemical Society; (USA)
·
OSTI ID:6725440
Mn(III)-Iodosylarene Porphyrins as an Active Oxidant in Oxidation Reactions: Synthesis, Characterization, and Reactivity Studies
Journal Article
·
Sun Aug 05 20:00:00 EDT 2018
· Inorganic Chemistry
·
OSTI ID:1476114
Nickel catalysis of olefin epoxidation
Journal Article
·
Tue Mar 24 23:00:00 EST 1987
· Inorg. Chem.; (United States)
·
OSTI ID:6630434
Related Subjects
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKENES
CATALYSIS
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMPLEXES
DATA
EPOXIDES
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LABELLING
LIGHT NUCLEI
NICKEL COMPLEXES
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDATION
OXYGEN 18
OXYGEN ISOTOPES
REACTION KINETICS
STABLE ISOTOPES
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
YIELDS
400201* -- Chemical & Physicochemical Properties
ALKENES
CATALYSIS
CATALYSTS
CATALYTIC EFFECTS
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COMPLEXES
DATA
EPOXIDES
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LABELLING
LIGHT NUCLEI
NICKEL COMPLEXES
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDATION
OXYGEN 18
OXYGEN ISOTOPES
REACTION KINETICS
STABLE ISOTOPES
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
YIELDS