Díaz-Urrutia Christian, Ott Timo
R&D Department, Chemicals Division, Grillo-Werke AG, Weseler Strasse 1, 47169 Duisburg, Germany.
Science. 2019 Mar 22;363(6433):1326-1329. doi: 10.1126/science.aav0177.
Direct methane functionalization to value-added products remains a challenge because of the propensity for overoxidation in many reaction environments. Sulfonation has emerged as an attractive approach for achieving the necessary selectivity. Here, we report a practical process for the production of methanesulfonic acid (MSA) from only two reactants: methane and sulfur trioxide. We have achieved >99% selectivity and yield of MSA. The electrophilic initiator based on a sulfonyl peroxide derivative is protonated under superacidic conditions, producing a highly electrophilic oxygen atom capable of activating a C-H bond of methane. Mechanistic studies support the formation of CH as a key intermediate. This method is readily scalable with reactors connected in series for prospective production of up to 20 metric tons per year of MSA.
由于在许多反应环境中存在过氧化倾向，将甲烷直接官能团化转化为增值产品仍然是一项挑战。磺化已成为实现所需选择性的一种有吸引力的方法。在此，我们报道了一种仅由两种反应物——甲烷和三氧化硫生产甲磺酸（MSA）的实用工艺。我们已实现了MSA >99%的选择性和产率。基于过氧磺酰衍生物的亲电引发剂在超酸性条件下被质子化，产生一个能够活化甲烷C-H键的高亲电氧原子。机理研究支持CH 作为关键中间体的形成。该方法易于通过串联反应器进行放大，有望每年生产高达20公吨的MSA。
