4-(Dimethylamino)pyridine as a catalyst for carbon acylation. 2. Control of carbon vs. oxygen acylation in benzofuranones

doi:10.1021/JO00233A022

Paper

4-(Dimethylamino)pyridine as a catalyst for carbon acylation. 2. Control of carbon vs. oxygen acylation in benzofuranones

Published Nov 1, 1987 · T. Black, S. Arrivo, J. S. Schumm

Journal of Organic Chemistry

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35

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Abstract

3-Phenylbenzofuranone (l), when deprotonated with sodium hydride and treated with excess chloroformates, generally affords products arising from oxygen acylation (enol carbonates 4). Such molecules, when treated with a catalytic quantity of 4-(dimethy1amino)pyridine (DMAP, 6) in halogenated solvents, rearrange to the carbon-acylated isomers 3. These migrations are proposed to involve the intermediacy of an acylated (dimethylamino)pyridmium species (lo), which transfers the ester functionality from oxygen to carbon. Inclusion of DMAP in the acylation reaction mixture, however. leads to direct carbon acylation. Thus, complete regiocontrolled acylation of these substrates is attainable.

Study Snapshot

4-(dimethy1amino)pyridine catalyzes regiocontrolled carbon acylation in benzofuranones, enabling complete control of oxygen and carbon acylation reactions.

PopulationOlder adults (50-71 years)

Sample size24

MethodsObservational

OutcomesBody Mass Index projections

ResultsSocial networks mitigate obesity in older groups.

Paper

4-(Dimethylamino)pyridine as a catalyst for carbon acylation. 2. Control of carbon vs. oxygen acylation in benzofuranones

References

Citations

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