A Para-Selective Kolbe-Schmitt Reaction.

ABSTRACT: The Kolbe-Schmitt reaction is the archetypal carboxylation reaction in organic synthesis yet generally suffers from the requirement of high temperatures and CO₂ pressures. We report a Kolbe-Schmitt-type carboxylation of phenols using near equimolar amounts of a CO₂ source at relatively low temperatures. The reaction uses the cesium salt of triphenylacetic acid as a combined source of base and CO₂. Whereas the traditional Kolbe-Schmitt reaction provides products of ortho carboxylation (salicylic acids), this method, which employs cesium salts, delivers high para selectivity to give 4-hydroxybenzoic acids. With the advantage of using near stoichiometric amounts of the carboxylating reagent, we demonstrate a practical and efficient preparation of ¹³

SUBMITTER: Liu X 

PROVIDER: S-EPMC12828480 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature