School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, P. R. China.
Research Center for Chemical Biology and Omics Analysis, Department of Chemistry, and Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, 1088 Xueyuan Blvd., Shenzhen, Guangdong 518055, P. R. China.
J Am Chem Soc. 2023 Mar 22;145(11):6310-6318. doi: 10.1021/jacs.2c12947. Epub 2023 Mar 9.
Herein, an unprecedented synthetic route to sulfilimines via a copper-catalyzed Chan-Lam-type coupling of sulfenamides is presented. A key to success in this novel transformation is the chemoselective -arylation of S(II) sulfenamides to form S(IV) sulfilimines, overriding the competitive, and more thermodynamically favored, C-N bond formation that does not require a change in the sulfur oxidation state. Computations reveal that the selectivity arises from a selective transmetallation event where bidentate sulfenamide coordination through the sulfur and oxygen atoms favors the -arylation pathway. The mild and environmentally benign catalytic conditions enable broad functional group compatibility, allowing a variety of diaryl or alkyl aryl sulfilimines to be efficiently prepared. The Chan-Lam coupling procedure could also tolerate alkenylboronic acids as coupling partners to afford alkenyl aryl sulfilimines, a class of scaffolds that cannot be directly synthesized via conventional imination strategies. The benzoyl-protecting groups could be conveniently removed from the product, which, in turn, could be readily transformed into several S(IV) and S(VI) derivatives.
本文提出了一种通过铜催化的 Chan-Lam 型磺酰胺偶联反应来合成亚磺酰亚胺的前所未有的方法。这种新型转化成功的关键在于选择性地对 S(II)磺酰胺进行芳基化，形成 S(IV)亚磺酰亚胺，从而抑制了不需要改变硫氧化态的更具热力学优势的竞争性 C-N 键形成。计算表明，选择性源于选择性的转金属化事件，其中通过硫和氧原子的双齿磺酰胺配位有利于芳基化途径。温和且环保的催化条件允许广泛的官能团兼容性，从而能够有效地制备各种二芳基或烷基芳基亚磺酰亚胺。Chan-Lam 偶联程序还可以容忍烯基硼酸作为偶联伙伴，从而得到烯基芳基亚磺酰亚胺，这一类支架不能通过传统的亚胺化策略直接合成。可以方便地从产物中去除苯甲酰基保护基团，反过来，该产物可以很容易地转化为几种 S(IV)和 S(VI)衍生物。
