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Access to "Friedel-Crafts-restricted" tert-alkyl aromatics by activation/methylation of tertiary benzylic alcohols.

ABSTRACT: Herein we describe a two-step protocol to prepare m-tert-alkylbenzenes. The appropriate tertiary benzylic alcohols are activated with SOCl(2) or concentrated HCl and then treated with trimethylaluminum, affording the desired products in 68-97% yields (22 examples). This reaction sequence is successful in the presence of a variety of functional groups, including acid-sensitive and Lewis-basic groups. In addition to t-Bu groups, 1,1-dimethylpropyl and 1-ethyl-1-methylpropyl groups can also be installed using this method.

SUBMITTER: Hartsel JA

PROVIDER: S-EPMC3321128 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Access to "Friedel-Crafts-restricted" tert-alkyl aromatics by activation/methylation of tertiary benzylic alcohols.

Hartsel Joshua A JA Craft Derek T DT Chen Qiao-Hong QH Ma Ming M Carlier Paul R PR

The Journal of organic chemistry 20120316 7

Herein we describe a two-step protocol to prepare m-tert-alkylbenzenes. The appropriate tertiary benzylic alcohols are activated with SOCl(2) or concentrated HCl and then treated with trimethylaluminum, affording the desired products in 68-97% yields (22 examples). This reaction sequence is successful in the presence of a variety of functional groups, including acid-sensitive and Lewis-basic groups. In addition to t-Bu groups, 1,1-dimethylpropyl and 1-ethyl-1-methylpropyl groups can also be inst ...[more]

PMID: 22394317

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