ISSN:
0570-0833
Keywords:
Stereochemistry
;
Heterolytic fragmentation
;
Fragmentation
;
Chemistry
;
General Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Heterolytic fragmentation can proceed by several mechanisms. A study of the solvolysis of γ-aminoalcohol derivatives N—C—C—C—X, where X equals halogen or —OSO2R, shows that fragmentation may occur by a one-step mechanism or by several multi-step mechanisms depending on structural, electronic, and steric factors. The one-step synchronous mechanism has rigorous stereoelectronic requirements. It is associated with an increased reaction rate as evidenced by the “frangomeric” effect. Ketoxime derivatives RR′C=N—X may undergo Beckmann fragmentation by the synchronous mechanism or by prior rearrangement depending on their α-substituents. Fragmentation is frequently accompanied by conventional substitution, elimination, and rearrangement reactions. Under such circumstances knowledge of all possible mechanisms of a given substrate is essential to bring about a desired transformation.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/anie.196905351
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