Iridium and Rhodium Complexes Containing Enantiopure Primary Amine-Tethered <i>N</i>-Heterocyclic Carbenes: Synthesis, Characterization, Reactivity, and Catalytic Asymmetric Hydrogenation of Ketones
作者:Kai Y. Wan、Florian Roelfes、Alan J. Lough、F. Ekkehardt Hahn、Robert H. Morris
DOI:10.1021/acs.organomet.7b00915
日期:2018.2.12
a bimetallic iridium compound with (S,S)-11 as the bridging ligand. This compound contains interesting NH···Cl and NH···Ir noncovalent intramolecular interactions. Salt (S,S)-12·HPF6 reacts with silver oxide to yield [Ag2((S,S)-12)2](PF6)2 (20). Reagent 20 serves as an efficient transmetalation reagent to deliver to each rhodium in [RhCl(cod)]2 1 equiv of (S,S)-12 as a bidentate ligand to give [Rh(cod)((S
咪唑鎓盐[(S,S)-t BuNC 3 H 3 NCHPhCHPhNH 2 ] PF 6,(S,S)-11· HPF 6是对映纯的“ Kaibene”配体t Bu-Kaibene ((S,S)-11在N-杂环卡宾(NHC)环-氮原子上具有叔丁基。通过将手性环状氨基磺酸酯与1-叔丁基咪唑回流,可以高产率和高纯度地制备它。同样((S,S)-12·在咪唑鎓环氮原子上具有异氰酸酯基的HPF 6以相同的方式制备,并用作Mes-Kaibene,(S,S)-12的来源。这些双齿Kaibene配体具有NHC和被手性接头隔开的伯胺。盐(S,S)-11· HPF 6或(S,S)-12· HPF 6与碱和AgI或CuI反应生成总共四个M(Kaibene) 2I化合物(M = Ag或Cu)。在22°C下,胺官能化的咪唑鎓阳离子经过氧化加成到[IrCl(cod)] 2(cod = 1,5-环辛二烯)中的铱(I),生