A mild and efficient catalytic method for FriedelâCrafts sulfonylation of arenes to the corresponding sulfones using a catalytic amount of reusable solid acid and arene- or alkanesulfonyl chlorides, sulfonic anhydrides and sulfonic acids as sulfonylating agents is described. Solid acids enable formation of a sulfone by the reaction of a sulfonic acid and an arene for the first time. In pursuit of the development of the best catalytic system, various metal-exchanged K10 montmorillonites and synthetic zeolites such as zeolite beta, zeolite Y and ZSM-5 have been screened for FriedelâCrafts sulfone synthesis. Fe3+-montmorillonite in the family of clays and zeolite beta in the family of zeolites exhibit higher activity. The activity is correlated to the presence of the right mix of Brønsted and Lewis acidic sites. The regioselective sulfonylation of toluene and naphthalene are studied in which para and beta selectivities are observed respectively.
本发明介绍了一种温和高效的催化方法,该方法使用催化量的可重复使用的固体酸以及作为磺化剂的炔或烷
磺酰氯、
磺酸酐和
磺酸,将
炔烃进行弗里德尔-卡夫斯磺化反应,生成相应的砜。固体酸首次使
磺酸和炔反应生成砜。为了开发最佳催化体系,研究人员筛选了各种
金属交换K10
蒙脱石和合成
沸石,如β
沸石、Y
沸石和ZSM-5,用于弗里德卡夫砜的合成。粘土家族中的 Fe3+
蒙脱石和
沸石家族中的β
沸石表现出更高的活性。这种活性与布氏酸性位点和
路易斯酸性位点的适当组合有关。对
甲苯和
萘的区域选择性磺化进行了研究,分别观察到对位选择性和β选择性。