Nickel(II) N‐Heterocyclic Carbene Complexes: Versatile Catalysts for C–C, C–S and C–N Coupling Reactions
作者:Lourdes Benítez Junquera、Francys E. Fernández、M. Carmen Puerta、Pedro Valerga
DOI:10.1002/ejic.201700057
日期:2017.5.18
A variety of Ni(II) complexes with a wide range of electronic and steric properties, bearing picolyl-imidazolidene ligands (a-g) and Cp (2a-f) or Cp* (3a,c,g) groups, have been synthesised and characterised using NMR and single crystal X-ray crystallography. The complexes have been used as precatalysts for a wide range of catalytic transformations most likely involving a Ni0/NiII catalytic cycle. In
A mild, scalable iodine-mediated oxidative cross-coupling reaction of arylhydrazines and thiols for construction of thioethers (sulfides) in the absence of any transition metals or photocatalysts is disclosed. A variety of unsymmetrical diaryl sulfides with broad substrate scope both on thiols and hydrazines were synthesized in high yields in water at room temperature. Furthermore, to demonstrate the
A highly active and magnetically retrievable nanoferrite–DOPA–copper catalyst for the coupling of thiophenols with aryl halides
作者:R. B. Nasir Baig、Rajender S. Varma
DOI:10.1039/c2cc17283f
日期:——
Diaryl sulfides were synthesized using a magnetically recoverable heterogeneous Cu catalystvia one-pot multi component reaction using MW irradiation; the use of isopropanol as a benign reaction medium, easy recovery of the catalyst using an external magnet, efficient recycling, and the high stability of the catalyst render the protocol economic and sustainable.
Organic synthesis via magnetic attraction: benign and sustainable protocols using magnetic nanoferrites
作者:R. B. Nasir Baig、Rajender S. Varma
DOI:10.1039/c2gc36455g
日期:——
Magnetic nano-catalysts have been prepared using simple modification of iron ferrites. The nm size range of these particles facilitates the catalysis process, as an increased surface area is available for the reaction; the easy separation of the catalysts by an external magnet and their recovery and reuse are additional beneficial attributes. Glutathione bearing nano-ferrites have been used as organocatalysts for the Paal–Knorr reaction and homocoupling of boronic acids. Nanoferrites, post-synthetically modified by ligands, were used to immobilize nanometals (Cu, Pd, Ru, etc.) which enabled the development of efficient, sustainable and green procedures for azide–alkynes-cycloaddition (AAC) reactions, C–S coupling, O-allylation of phenol, Heck-type reactions and hydration of nitriles.
Copper-catalyzed Ullmann coupling under ligand- and additive-free conditions. Part 2: S-Arylation of thiols with aryl iodides
作者:Pongchart Buranaprasertsuk、Joyce Wei Wei Chang、Warinthorn Chavasiri、Philip Wai Hong Chan
DOI:10.1016/j.tetlet.2008.01.060
日期:2008.3
S-Arylation of a wide variety of substituted aryl and aliphatic thiols with aryl halides catalyzed by copper iodide under mild ligand- and additive-free conditions (nBu4NBr, PhMe, NaOH, reflux, 22 h) is accomplished in good to excellent product yields (up to 96%).
在温和的无配体和无添加剂条件下(n Bu 4 NBr,PhMe,NaOH,回流,22 h),将各种取代的芳基和脂肪族硫醇与碘化铜催化的芳基卤化物进行S-芳基化反应产品收率(高达96%)。