Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, 48149 Münster, Germany.
J Am Chem Soc. 2011 Mar 16;133(10):3312-5. doi: 10.1021/ja111483r. Epub 2011 Feb 22.
Merging cooperative Si-H bond activation and electrophilic aromatic substitution paves the way for C-3-selective indole C-H functionalization under electronic and not conventional steric control. The Si-H bond is heterolytically split by the Ru-S bond of a coordinatively unsaturated cationic ruthenium(II) complex, forming a sulfur-stabilized silicon electrophile. The Wheland intermediate of the subsequent Friedel-Crafts-type process is assumed to be deprotonated by the sulfur atom, no added base required. The overall catalysis proceeds without solvent at low temperature, only liberating dihydrogen.
协同 Si-H 键活化和亲电芳香取代为电子而非传统空间控制下 C-3 选择性吲哚 C-H 功能化铺平了道路。Si-H 键被配位不饱和的阳离子钌（II）配合物的 Ru-S 键异裂，形成硫稳定的硅亲电试剂。随后的 Friedel-Crafts 型反应的 Wheland 中间体被硫原子去质子化，无需添加额外的碱。整个催化过程在低温下、无溶剂、仅释放氢气的条件下进行。
