A Mechanistic Investigation into the Zinc Carbenoid-mediated Homologation Reaction by DFT methods: Is a Classical Donor-Acceptor Cyclopropane Intermediate Involved?
Abstract
An extensive density functional theory (DFT, M05-2X) investigation has been performed on the zinc carbenoid-mediated homologation reaction of β-keto esters. The mechanistic existence of a classical donor−acceptor cyclopropane intermediate was probed to test the traditional school of thought regarding these systems. Calculations of the carbenoid insertion step, following enolate formation, unmasked two possible pathways. Pathway B was shown to explain the proposed, but spectroscopically unobservable donor−acceptor cyclopropane intermediate, while the second (pathway A) reveals an alternative to the classical intermediate in that a cyclopropane transition state leads to product.
Department
Chemistry
Publication Date
11-1-2010
Journal Title
Journal of Organic Chemistry
Publisher
American Chemical Society
Digital Object Identifier (DOI)
10.1021/jo101590t
Document Type
Article
Recommended Citation
A Mechanistic Investigation into the Zinc Carbenoid-mediated Homologation Reaction by DFT methods: Is a Classical Donor-Acceptor Cyclopropane Intermediate Involved? Eger, W.; Zercher, C. K.; Williams, C. M. Org. Chem. 2010, 75, 7322-7331. PMCID: PMC3237639
Rights
Copyright © 2010, American Chemical Society