ISSN:
0894-3230
Keywords:
Organic Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The Wittig and anoinic Claisen rearrangements of deprotonated allyl phenyl ether, PhOC̄HCH=CH2, were investigated by MO theory employing the AM1 method. The most favoured reaction pathway for the Wittig rearrangement is the intramolecular SNAr process proceeding by the addition-elimination mechanism involving a Meisenheimer complex-type, three-membered-ring intermediate. For the anionic Claisen rearrangement a three-step mechanism is favoured, in which the intramolecular proton transfer occurs first from the ortho position of the phenyl ring to the anionic carbon centre, which is then followed by a process involving a six-membered ring intermediate. The two types of rearrangements can compete, but the Wittig type is more facile and favoured than the Claisen process owing to the lower activation enthalpy. The results are in good agreement with gas-phase experimental results.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/poc.610051206
