Hydroxybenzoates are an important class of phenols that are widely used as preservatives
and antiseptics in the food and pharmaceutical industries. In this report, a facile
preparation of 2,6- and 2,3-disubstituted 4/5-hydroxybenzoates by iridium-catalyzed
borylation of respective disubstituted benzoate esters followed by oxidation is described.
This synthetic route allows for the incorporation of halogens in the final hydroxybenzoates
with substitution patterns not readily accessible by the traditional routes of aromatic
functionalization.
Key words
iridium-catalyzed C–H borylation - oxidation - Oxone
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- hydroxybenzoates - parabens - preservatives - halogen - trifluoromethyl