Catalyst-free reactions employing renewable resources are needed for sustainable development. For example, biologically important β-keto sulfones have been recently synthesized by decarboxylative-coupling reaction between arylpropiolic acids and sulfonic acid derivatives. Nonetheless, existing protocols involve harsh conditions, complicated work-up, and the use of metal catalysts and extra oxidants. To address these shortcomings, we propose here catalyst-free decarboxylative oxysulfonylations of arylpropiolic acids employing air as a green oxidant. Arylpropiolic acids and sodium sulfinates are mixed in the hexafluoroisopropanol solvent under an aerobic atmosphere at room temperature. The results show that β-keto sulfones are formed in 60–97% yields. The products are purified by simple recrystallization. This method is also used to the direct synthesis of bioactive agents and the late-stage functionalization of an estrone derivative.

可持续发展需要使用可再生资源的无催化剂反应。例如，最近已通过芳基丙炔酸和磺酸衍生物之间的脱羧偶联反应合成了生物学上重要的 β-酮基砜。尽管如此，现有协议涉及恶劣的条件、复杂的后处理以及金属催化剂和额外氧化剂的使用。为了解决这些缺点，我们在此提出使用空气作为绿色氧化剂的芳基丙醇酸的无催化剂脱羧氧磺酰化。芳基丙醇酸和亚磺酸钠在室温下在有氧气氛下在六氟异丙醇溶剂中混合。结果表明，β-酮砜的形成率为 60-97%。产物通过简单的重结晶纯化。