Dub Pavel A, Matsunami Asuka, Kuwata Shigeki, Kayaki Yoshihito
Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1-E4-1 O-okayama , Meguro-ku , Tokyo 152-8552 , Japan.
J Am Chem Soc. 2019 Feb 13;141(6):2661-2677. doi: 10.1021/jacs.8b12961. Epub 2019 Feb 4.
The asymmetric transfer hydrogenation (ATH) of ketones/imines with Noyori-Ikariya catalyst represents an important reaction in both academia and fine chemical industry. The method allows for the preparation of chiral secondary alcohols/amines with very good to excellent optical purities. Remarkably, the same chiral Noyori-Ikariya complex is also a precatalyst for a wide range of other chemo- and stereoselective reductive and oxidative transformations. Among them are enantioselective sulfonamidation of acrylates (intramolecular aza-Michael reaction) and carboxylation of indoles with CO. Development of these catalytic reactions has been inspired by the realized cleavage of the N-H bond of sulfonamides and indoles by the 16e amido derivative of the 18e precatalyst via metal-ligand cooperation (MLC). This paper summarizes our efforts to investigate N-H bond cleavage of gaseous ammonia in solution via MLC and reports the serendipitous discovery of a new class of chiral tridentate κ[ N, N', N″] Ru and Ir metallacycles, derivatives of the famous M-FsDPEN catalysts (M = Ru, Ir). The protonation of these metallacycles by strong acids containing weakly coordinating (chiral) anions generates ionic complexes, which were identified as conceptually novel Noyori-Ikariya precatalysts. For example, the ATH of aromatic ketones with some of these complexes proceeds with up to 99% ee.
使用野依-伊贺谷催化剂对酮/亚胺进行不对称转移氢化（ATH）在学术界和精细化工领域都是一个重要的反应。该方法能够制备出光学纯度非常好至优异的手性仲醇/胺。值得注意的是，同样的手性野依-伊贺谷配合物也是多种其他化学和立体选择性还原及氧化转化反应的前催化剂。其中包括丙烯酸酯的对映选择性磺酰胺化反应（分子内氮杂迈克尔反应）以及吲哚与CO的羧基化反应。这些催化反应的发展受到了18e前催化剂的16e酰胺衍生物通过金属-配体协同作用（MLC）实现磺酰胺和吲哚N-H键断裂的启发。本文总结了我们通过MLC研究溶液中气态氨N-H键断裂的工作，并报道了意外发现的一类新型手性三齿κ[ N, N', N″] Ru和Ir金属环，它们是著名的M-FsDPEN催化剂（M = Ru, Ir）的衍生物。这些金属环被含弱配位（手性）阴离子的强酸质子化生成离子配合物，这些离子配合物被确定为概念上新颖的野依-伊贺谷前催化剂。例如，使用其中一些配合物对芳香酮进行ATH反应时，对映体过量值可达99%。
