The Indium and Zinc-Mediated Acyloxyallylation of Protected and Unprotected Aldotetroses - Revealing a Pronounced Diastereodivergence and a Fundamental Difference in the Performance of the Mediating Metal

Draskovits, Markus; Stanetty, Christian; Baxendale, Ian R.; Mihovilovic, Marko D.

Abstract

The acyloxyallylation of unprotected aldoses was first demonstrated more than a decade ago as a potentially elegant two-carbon homologation of reducing sugars (upon ozonolysis); however, its application in real case syntheses remained scarce. Following up on such a successful showcase and to answer several pending questions about this attractive transformation, we engaged in an in depth methodological reinvestigation. The epimeric tetroses l-erythrose and d-threose in unprotected and protected form were successfully applied to the indium and also zinc-mediated acyloxyallylation, with the latter being a first for an unprotected sugar. The investigation largely benefited from the choice of these more exotic starting materials as it allowed unambiguous identification/quantification of the hexose-products which are available as authentic reference materials. The observed diastereoselectivities indicate a strong substrate control (stereochemistry at O2), and the influence of the reagent’s structure on the selectivity was investigated in great detail. A strong facial diastereodivergence between related protected and unprotected structures was demonstrated and an unexpected, pronounced principle difference in performance between indium and zinc was revealed.

Citation

Draskovits, M., Stanetty, C., Baxendale, I. R., & Mihovilovic, M. D. (2018). The Indium and Zinc-Mediated Acyloxyallylation of Protected and Unprotected Aldotetroses - Revealing a Pronounced Diastereodivergence and a Fundamental Difference in the Performance of the Mediating Metal. Journal of Organic Chemistry, 83(5), 2647-2659. https://doi.org/10.1021/acs.joc.7b03063

• Journal Article Type: Article
• Acceptance Date: Jan 25, 2018
• Online Publication Date: Jan 25, 2018
• Publication Date: Mar 2, 2018
• Deposit Date: Feb 1, 2018
• Publicly Available Date: Feb 16, 2018
• Journal: Journal of Organic Chemistry
• Print ISSN: 0022-3263
• Electronic ISSN: 1520-6904
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 83
• Issue: 5
• Pages: 2647-2659
• DOI: https://doi.org/10.1021/acs.joc.7b03063
• Public URL: https://durham-repository.worktribe.com/output/1335641