Relative Rates of Transesterification vis-à-vis Newman's Rule of Six.

J Org Chem

Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States.

Published: September 2024

The relative reactivity of a systematic series of simple aliphatic acetate esters has been measured. Exposure of pairs of esters of increasing remote steric hindrance (by altering the degree of branching of the ester alkyl group) to a methanolic solution of CsCO proved to be a reliable (and general) method for quantitating the rate differences in these base-catalyzed transesterification reactions. The trends in relative rates are in accordance with the qualitative "Rule of Six" put forward by Melvin S. Newman in 1950, as deduced then from interpretation of earlier reports of ease of Fischer esterification reactions.

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http://dx.doi.org/10.1021/acs.joc.4c01673DOI Listing

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