An environmentally-friendly one-pot synthesis of 4-sulfonyl benzoic acids

This Letter reports an environmentally-friendly one-pot S_NAr reaction of thiols to 4-halobenzoic acid methyl esters to provide 4-substituted sulfone benzoic acids and picolinic acids after bleach-mediated oxidative workup. These acid intermediates were synthesized on gram scale, are perfect partners for library synthesis, and have good physical chemical properties useful for drug discovery.