Kawazu Ryohei, Torigoe Takeru, Kuninobu Yoichiro
Department of Molecular and Material Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga-shi, Fukuoka 816-8580, Japan.
Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasugakoen, Kasuga-shi, Fukuoka, 816-8580, Japan.
Angew Chem Int Ed Engl. 2022 May 23;61(22):e202202327. doi: 10.1002/anie.202202327. Epub 2022 Mar 29.
New ligands for the iridium-catalyzed C(sp )-H borylation of aliphatic compounds were established. In sharp contrast to 6-methyl-2,2'-bipyridine and 6-isobutyl-2,2'-bipyridine, 2,2'-bipyridine and 1,10-phenanthroline derivatives bearing a hydrosilylmethyl group (which would give a thermally stable NNSi pincer complex) served as suitable ligands for the reaction. Among them, a phenanthroline-based NNSi pincer ligand was shown to be an excellent ligand, and various aliphatic compounds were efficiently converted to the corresponding borylated products using the Ir/NNSi pincer catalyst system. The NNSi pincer ligand showed unique selectivity and enabled the iridium-catalyzed C(sp )-H borylation using pinacolborane [H-B(pin)] instead of B (pin) . The formation of an iridium complex bearing a quinoline-based NNSi pincer ligand from [IrCl(cod)] was observed, and the catalytic activity of the complex was demonstrated.
已开发出用于铱催化脂肪族化合物C(sp³)-H硼化反应的新型配体。与6-甲基-2,2'-联吡啶和6-异丁基-2,2'-联吡啶形成鲜明对比的是，带有氢硅烷基甲基的2,2'-联吡啶和1,10-菲咯啉衍生物（可形成热稳定的NNSi钳形配合物）是该反应的合适配体。其中，一种基于菲咯啉的NNSi钳形配体表现出优异的性能，使用Ir/NNSi钳形催化剂体系可将各种脂肪族化合物高效转化为相应的硼化产物。该NNSi钳形配体具有独特的选择性，能够实现铱催化使用频哪醇硼烷[H-B(pin)]而非B(pin)₂的C(sp³)-H硼化反应。观察到由[IrCl(cod)]形成了带有喹啉基NNSi钳形配体的铱配合物，并证明了该配合物的催化活性。
