12221-03-3Relevant articles and documents
Bio-inspired noble metal-free reduction of nitroarenes using NiS2+x/g-C3N4
Zhang, Ya-Nan,Li, Xin-Hao,Cai, Yi-Yu,Gong, Ling-Hong,Wang, Kai-Xue,Chen, Jie-Sheng
, p. 60873 - 60877 (2014)
We introduce the concept of bio-inspired catalytic hydrogenation of nitroarenes by mimicking the catalytic behavior of enzymes with NiS2+x nanoparticles and polymeric melon (g-C3N4). The g-C3N4-supported NiS2+x nanoparticles functioned as ligand-free and noble metal-free catalysts and offered high efficiency, comparable to noble metal-based catalysts, but at a much better selectivity.
Catalytic Deoxygenation of Nitroarenes Mediated by High-Valent Molybdenum(VI)-NHC Complexes
Liu, Shenyu,Amaro-Estrada, Jorge Ivan,Baltrun, Marc,Douair, Iskander,Schoch, Roland,Maron, Laurent,Hohloch, Stephan
supporting information, p. 107 - 118 (2021/02/05)
The high-valent molybdenum(VI) N-heterocyclic carbene complexes, (NHC)MoO2 (1) and (NHC)MoO(NtBu) (2) (NHC = 1,3-bis(3,5-di-tert-butyl-2-phenolato)-benzimidazol-2-ylidene), are investigated toward their catalytic potential in the deoxygenation of nitroarenes. Using pinacol as the sacrificial and green reductant, both complexes are shown to be very active (pre)catalysts for this transformation allowing a reduction of the catalyst loading down to 0.25 mol %. Mechanistic investigations show μ-oxo bridged molybdenum(V) complexes [(NHC)MoO]2O (4) and [(NHC)Mo(NtBu)]2O (5) as well as zwitterionic pinacolate benzimidazolium complex 6, with a doubly protonated NHC ligand, to be potentially active species in the catalytic cycle. Both 4 and 5 can be prepared independently by the deoxygenation of 1 and 2 using triethyl phosphine (PEt3) or triphenyl phosphine (PPh3) and were shown to exhibit an unusual multireferenced ground state with a very small singlet-triplet gap at room temperature. Computational studies show that the spin state plays an unneglectable role in the catalytic process, efficiently lowering the reaction barrier of the deoxygenation step. Mechanistic details, putting special emphasis on the fate of the catalyst will be presented and potential routes how nitroarene reduction is facilitated are evaluated.
Synthesis and characterization of chitosan pyridyl imine palladium (CPIP) complex as green catalyst for organic transformations
Chundawat, Narendra Singh,Pathan, Sultan,Singh, Girdhar Pal,Deuri, Arup Saha,Zarrintaj, Payam,Chauhan, Narendra Pal Singh
, p. 2835 - 2850 (2021/02/11)
In this work, the modification of chitosan using 2-acetyl pyridine has been used to prepare an intermediate, chitosan pyridyl imine (CPI), in first step and then in second step it is further reacted with Pd(OAc)2 to develop chitosan pyridyl imine palladium (CPIP) complex catalyst in a very simplistic way. The formed CPIP has been extensively characterized with respect to raw chitosan utilizing methods including FT-IR, pyrolysis GC–MS, XRD, XPS, FE-SEM, EDS, TGA-DTG and DSC. TG-DSC study suggested that the catalyst is thermally stable up to 300?°C. This catalyst shows an excellent activity in the reduction of toxic pollutant nitrobenzene to less toxic aniline. CPIP complex has also been found to give magnificent results in Suzuki–Miyaura and Heck cross-coupling reactions, and therefore, using this green catalyst, the toxic phosphine ligand can be excluded from cross-coupling reactions. This study furnishes an economic and eco-friendly catalyst for organic transformation in sustainable chemistry.
