ISSN:
0570-0833
Keywords:
Kinetics
;
Dipolar cycloaddition
;
Cycloaddition
;
Heterocycles
;
Reaction mechanisms
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Criteria for the mechanism of 1,3-dipolar cycloadditions which lead to 5-membered rings are provided by the stereoselectivity observed with cis-trans isomeric dipolarophiles, by the effect of solvent and substituents on the rate constants, by the activation parameters, and by orientation phenomena. A concerted addition, which can also be described in terms of molecular orbitals and in which the two new σ-bonds are formed simultaneously, although not necessarily at equal rates, offers the best explanation of the experimental facts.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/anie.196306331
Permalink