Intramolecular reactions of metal carbenoids with allylic ethers: is a free ylide involved in every case?

Clark, J. S. and Hansen, K. E. (2014) Intramolecular reactions of metal carbenoids with allylic ethers: is a free ylide involved in every case? Chemistry: A European Journal, 20(18), pp. 5454-5459. (doi: 10.1002/chem.201304054) (PMID:24648216)

Abstract

Rhodium-, copper- and iridium-catalyzed reactions of the ¹³C-labelled diazo carbonyl substrates 18* and 19* were performed. Results obtained from copper- and iridium-catalyzed reactions of the ¹³C -labelled α-diazo β-keto ester 19* indicate that either or both of these reactions do not proceed via a free oxonium ylide but instead follow a competing non-ylide route that delivers apparent [2,3]-sigmatropic rearrangement products. In the case of the iridium-catalyzed reaction of α-diazo β-keto ester 19*, results obtained from crossover experiments indicate that the initially formed metal-bound ylide dissociates to give an iridium enolate and an allyl cation, which recombine to form the C C bond.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Clark, Professor Stephen and Hansen, Miss Karin
• Authors: Clark, J. S., and Hansen, K. E.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Chemistry: A European Journal
• Publisher: Wiley-VCH Verlag
• ISSN: 0947-6539
• ISSN (Online): 1521-3765
• Copyright Holders: Copyright © 2014 Wiley
• First Published: First published in Chemistry: A European Journal 20(18):5454-5459
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher.