Cyclometalated iridium complexes are shown to be excellent catalysts for transferhydrogenation of carbonyl compounds in water using formate as a hydrogen source. A wide range of ketones and aldehydes have been reduced at 0.05% catalyst loading with no need for any organic solvents. Solution pH is found to play a critical role, with acidic conditions needed for fasttransferhydrogenation.
A copper-catalyzed cycloamination of α-Csp3–H bond of N-aryl ketimines with sodium azide has been developed. This methodology provides an efficient access to quinoxalines and features mild reaction conditions and readily available ketimines with diverse functional group tolerance.
A novel Rh(iii)-catalyzed relay cross-coupling cascade between arylketoimines and diazoesters is described. This transformation provides a concise access to unique π-conjugated 1-azaphenalenes (1-APLEs) via a double aryl Csp2–H bond carbenoid functionalization process.
Abstract A series of novel [3]ferrocenophane-derived N/BfrustratedLewispairs (FLPs) were synthesized and successfully applied to the catalytic hydrogenation of imines in 71-93% yields. This approach could be easily conducted on gram scale and provided versatile synthetic route for the key intermediate of sertraline hydrochloride without heavy metal residues. Graphical Abstract
Simple, efficient and reusable Pd–NHC catalysts for hydroamination
作者:Qian Chen、Lanlan Lv、Meng Yu、Yanhui Shi、Yuling Li、Guangsheng Pang、Changsheng Cao
DOI:10.1039/c3ra42990c
日期:——
series of chelating NHC–palladium complexes with different alkane-bridges of the type Pd[NHC–(CH2)n–NHC]X2 (X = Br or Cl, n = 2–4) were synthesized, where NHC is a triazolyl-N-heterocyclic carbene donor ligand. The bromide complexes with n = 2 and 3 were characterized by X-ray crystallography. The effects of the length of the bridge and halide ligand on the catalytic reactivity in the hydroamination reaction