Campus Units

Chemistry

Document Type

Article

Publication Version

Published Version

Publication Date

12-31-2009

Journal or Book Title

The Journal of Organic Chemistry

Volume

75

Issue

3

First Page

897

Last Page

901

DOI

10.1021/jo902333y

Abstract

A variety of iodo-substituted isochromenes, dihydroisobenzofurans, and pyranopyridines are readily prepared in good to excellent yields under mild conditions by the iodocyclization of readily available 2-(1-alkynyl)benzylic alcohols or 2-(1-alkynyl)-3-(hydroxymethyl)pyridines. Reactions are carried out in MeCN at 25 °C with 3 equiv of I2 as the iodine source and NaHCO3 (3 equiv) as the base. The regiochemical outcome of the reaction strongly depends on the substitution pattern of the starting material. In particular, the 5-exo-dig cyclization mode, leading to dihydroisobenzofurans, is observed in the case of substrates bearing a tertiary alcoholic group, owing to the gem-dialkyl effect, while the 6-endo-dig cyclization mode, leading to isochromene or pyranopyridines, is the usually preferred pathway in the case of substrates bearing a primary or secondary alcoholic group.

Comments

Reprinted (adapted) with permission from The Journal of Organic Chemistry, 75(3); 897-901. Doi: 10.1021/jo902333y. Copyright 2009 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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