Work

Alkynylation of Pentose Derivatives with Stereochemical Fidelity: Implications for the Regioselectivity of Alkynyl Diol Cycloisomerizations to Cyclic Enol Ethers

Year: 2019

Type: article

Abstract: This work characterizes a previously undetected epimerization in the preparation of alkynyl diols from pentose precursors utilizing the Ohira-Bestmann reagent. Lithium trimethylsilyldiazomethane (Colvin reagent) additions to the d-ribose and d-lyxose-derived benzylidene acetals provide the respective alkynyl diol stereoisomers, without epimerization. Regioselective tungsten-catalyzed cycloisomerizations of the d-ribose- and d-lyxose-derived alkynyl diols yield rigid bicyclic pyranose glycals, confirming the stereochemical fidelity of the Colvin alkynylation process.

Source: Organic Letters

DOI: 10.1021/acs.orglett.9b01024

Authors: Frank E. McDonald, Dian Ding, Andrew J. Ephron, John Bacsa

Institution: Emory University

Language: English

Topic: Carbohydrate Chemistry and Synthesis

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: Emory University, National Institute of General Medical Sciences

Award: Overcoming Steric Challenges in Glycosylations