Cycloaddition reactions of allenes with N-phenylmaleimide. A two-step, diradical-intermediate process
The stereoselectivities, chemoselectivities, relative reactivities, and kinetic isotope effects have been determined in the cycloaddition reactions of substituted allenes with N-phenylmaleimide. The comparison of these results with those derived from the studies of the cycloaddition of 1,1-dichloro-2,2-difluoroethene and the radical-chain addition of benzenethiol to allenes strongly indicates that the cycloadditions with N-phenylmaleimide occur via a two-step, diradical-intermediate process. The stereochemical features controlling the formation of the stereoisomeric diradical intermediates and their ring closures are discussed. In addition to the cycloaddition processes, competitive ene reactions occur to produce intermediate dienes, which react further to produce 1:2 adducts or nonreactive alkyne-containing 1:1 adducts. These ene reactions also appear to proceed via diradical intermediates.
- Research Organization:
- Univ. of Notre Dame, IN
- OSTI ID:
- 6720375
- Journal Information:
- J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 104:13; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
400302* -- Organic Chemistry-- Isotope Effects-- (-1987)
ADDUCTS
ALKENES
ALLENE
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
CYCLOALKENES
DATA
DEUTERIUM
DIENES
ELEMENTS
EXPERIMENTAL DATA
HYDROCARBONS
HYDROGEN
HYDROGEN ISOTOPES
IMIDES
INFORMATION
ISOTOPE EFFECTS
ISOTOPES
KINETICS
LIGHT NUCLEI
MAGNETIC RESONANCE
MASS SPECTROSCOPY
NONMETALS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
POLYENES
REACTION KINETICS
RESONANCE
SPECTROSCOPY
STABLE ISOTOPES