ISSN:
0570-0833
Keywords:
Metathesis
;
Reaction mechanisms
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
In this paper views regarding the nature of the transition state in olefin metathesis are discussed. Earlier concepts that assumed a pairwise scrambling mechanism have been recently challenged. Metathesis studies involving acyclic as well as cyclic olefins have been reported which strongly suggest a chain process that may involve a carbene-to-metallocycle interconversion as the pathway responsible for transalkylidenation. Catalytic systems that display a low apparent metathesis activity on terminal olefins display a unique specificity in cross reactions with internal olefins. Critical experiments indicate that terminal olefins rapidly undergo regenerative metathesis preferentially. Results suggest that in the transient metallocycle, the most stringent steric requirements occur at the β-carbon, although the origin of this steric demand is not obvious.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/anie.197604011
