5877-51-0Relevant articles and documents
Redox-Neutral Imination of Alcohol with Azide: A Sustainable Alternative to the Staudinger/Aza-Wittig Reaction
Li, Huaifeng,Lupp, Daniel,Das, Pradip K.,Yang, Li,Gon?alves, Théo P.,Huang, Mei-Hui,El Hajoui, Marwa,Liang, Lan-Chang,Huang, Kuo-Wei
, p. 4071 - 4076 (2021/04/12)
The traditional Staudinger/aza-Wittig reaction represents one of the most powerful tools for imine formation. However, for this multistep procedure, the sacrificial phosphine has to be used, resulting in difficulties in the purification process and waste disposal at the same time. Here, we report a redox-neutral azide-alcohol imination methodology enabled by a base-metal nickel PN3 pincer catalyst. The one-step, waste-free, and high atom-economical features highlight its advantages further. Moreover, mechanistic insight suggests a non-metal-ligand cooperation pathway based on the observation of an intermediate and density functional theory calculations.
Ionic-Liquid-Catalyzed Synthesis of Imines, Benzimidazoles, Benzothiazoles, Quinoxalines and Quinolines through C?N, C?S, and C?C Bond Formation
Adimurthy, Subbarayappa,Badhani, Gaurav,Joshi, Abhisek
, p. 6705 - 6716 (2021/12/31)
We report the tetramethyl ammonium hydroxide catalyzed oxidative coupling of amines and alcohols for the synthesis of imines under metal-free conditions by utilizing oxygen from air as the terminal oxidant. Under the same conditions, with ortho-phenylene diamines and 2-aminobenzenethiols the corresponding benzimidazoles and benzothiazoles were obtained. Quinoxalines were obtained from ortho-phenylene diamines and 1-phenylethane-1,2-diol, the conditions were then extended to the synthesis of quinoline building blocks by reaction of 2-amino benzyl alcohols either with 1-phenylethan-1-ol or acetophenone derivatives. The formation of C?N, C?S and C?C bonds was achieved under metal-free conditions. A broad range of amines (aromatic, aliphatic, cyclic and heteroaromatic) as well as benzylic alcohols including heteroaryl alcohols reacted smoothly and provided the desired products. The mild reaction conditions, commercially available catalyst, metal-free, good functional-group tolerance, broad range of products (imines, benzimidazoles, benzothiazoles, quinoxalines and quinolines) and applicability at gram scale reactions are the advantages of the present strategy.
A novel water-dispersible and magnetically recyclable nickel nanoparticles for the one-pot reduction-Schiff base condensation of nitroarenes in pure water
Ghamari Kargar, Pouya,Ravanjamjah, Asiye,Bagherzade, Ghodsieh
, p. 1916 - 1933 (2021/07/10)
In this work, a heterogeneous nanocatalyst called Ni-Fe3O4@Pectin~PPA ~ Piconal was first synthesized, which was investigated as a bifunctional catalyst containing nickel functional groups. On the other hand, this Ni-Fe3O4@Pectin~PPA ~ Piconal catalyst in aqueous solvents shows a very effective performance at ambient temperature for the nitroarene reduction reaction with sodium borohydride, for which NaBH4 is considered as a reducing agent. This is a novelty magnetic catalyst that was approved by various methods, including Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), Dynamic light scattering (DLS), Transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), Inductively coupled plasma (ICP), Energy-dispersive X-ray spectroscopy (EDX), and Field emission scanning electron microscopy (FESEM) analyses. From the satisfactory results obtained from the reduction of nitrogen, this catalytic system is used for a one-pot protocol containing a reduction-Schiff base concentration of diverse nitroarenes. It was corroborated with the heterogeneous catalytic experiments on the one-pot tandem synthesis of imines from nitroarenes and aldehydes. Finally, the novel Ni-Fe3O4@Pectin~PPA ~ Piconal catalyst could function as a more economically desirable and environmentally amicable in the catalysis field. The favorable products are acquired in good to high performance in the attendance of Ni-Fe3O4@Pectin~PPA ~ Piconal as a bifunctional catalyst. This catalyst can be recycled up to six steps without losing a sharp drop.
Visible-Light-Induced Cycloaddition of α-Ketoacylsilanes with Imines: Facile Access to β-Lactams
Ye, Jian-Heng,Bellotti, Peter,Paulisch, Tiffany O.,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 13671 - 13676 (2021/05/11)
We report the synthesis of β-lactams from α-ketoacylsilanes and imines, which proceeds via a formal [2+2] photochemical cycloaddition with in situ generation of siloxyketene. This mild and operationally simple reaction proceeds in an atom-economic fashion with broad substrate scope, including aldimines, ketimines, hydrazones, and fused nitrogen heterocycles, affording a variety of important β-lactams with satisfactory diastereoselectivities in most cases. This reaction also features good functional-group tolerance, facile scalability and product diversification. Experimental and computational studies suggest that α-ketoacylsilanes can serve as photochemical precursors by engaging in a 1,3 silicon shift to the distal carbonyl group.
Aza-peterson olefinations: Rapid synthesis of (E)-alkenes
Britten, Thomas K.,Basson, Ashley J.,Roberts, Dean D.,McLaughlin, Mark G.
, p. 3535 - 3544 (2021/06/03)
An aza-Peterson olefination methodology to access 1,3-dienes and stilbene derivatives from the corresponding allyl- or benzyltrimethylsilane is described. Silanes can be deprotonated using Schlosser's base and added to N -phenyl imines or ketones to directly give the desired products in high yields.
Thiazoline-Iridium (III) Complexes and Immobilized Nanomaterials as Selective Catalysts in N-Alkylation of Amines with Alcohols
Denizalt?, Serpil,Dayan, Serkan,Günnaz, Salih,?ahin, Ertan
, (2020/10/02)
In this research, a new series of thiazoline-iridium (III) complexes (4–7) derived from cysteine were prepared and fully characterized by conventional methods. The molecular structure of complex 5 was also determined by single-crystal X-ray diffraction. These complexes were evaluated as catalysts for hydrogen-borrowing reactions of amines with alcohols. In particular, complex 5 showed the best activity as catalyst. Various amines have been alkylated with alcohols affording moderate to good yield (33–99%). Moreover, the immobilized nanomaterials (M1,2) were fabricated by sonication process from the best catalyst 5 with the multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO), respectively, and characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) spectroscopy, and inductively coupled plasma-mass spectrometry (ICP-MS). The M1,2 nanomaterials were also tested as catalysts in model catalytic reaction for N-alkylation. The M1 nanomaterial showed significantly higher activity than the M2 nanomaterial. The M1 catalyst was recovered by filtration and reused for four catalytic cycles with high conversion (99%, 97%, 96%, and 86%).
Method for synthesizing aluminum phosphate molecular sieve catalytic imine
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Paragraph 0035-0037, (2020/06/02)
The invention discloses a method for catalyzing synthesis of an imine by using an aluminum phosphate molecular sieve, and belongs to the technical field of catalytic synthesis of imines. Under the action of an HP-MeAlPO-5 molecular sieve, air or oxygen is used as an oxidant, and an amine and an alcohol which contain different substituents are directly subjected to oxidative coupling to synthesizethe imine under mild conditions. According to the method provided by the invention, the reaction conditions of the adopted catalytic system are mild, and the TOF is high; a reaction can efficiently catalyze the synthesis of the imine at room temperature under air; and the method can adopt transition metals, which are cheap and easy to obtain, such as iron, cobalt and nickel as a molecular sieve dopant, and the availability of the molecular sieve is improved.
Simple synthesis of the novel Cu-MOF catalysts for the selective alcohol oxidation and the oxidative cross-coupling of amines and alcohols
Ghamari Kargar, Pouya,Aryanejad, Sima,Bagherzade, Ghodsieh
, (2020/09/11)
A novel porous metal–organic framework {Cu2(bbda)0.5(Hbbda)1.5(OAc)1.5.8H2O} (UoB-5) was synthesized under ultrasound irradiation by employing a new Schiff base ligand H2bbda (4,4'(1,4-phenylene bis (azanylylidene)) bis (methanylylidene))dibenzoic acid) and was fully characterized. The microporous nature of UoB-5 was confirmed by gas-sorption measurements. This framework acted as a highly effective heterogeneous catalyst for the alcohol oxidation reaction with tert-butyl hydroperoxide (t-BuOOH) as an oxidant. The presence of coordinatively unsaturated metal sites in UoB-5 could be the reason for high performance in this reaction. Furthermore, using the long linker with the free -NC group and uncoordinated -N atom on the wall of the pores created UoB-5 an excellent candidate for the catalytic activities without activation of the framework. It was confirmed with the heterogeneous catalytic experiments on the one-pot tandem synthesis of imines from benzyl alcohols and anilines. Eventually, the new Cu-MOF (UoB-5) could be an alternative catalyst as a more economically favorable and environmentally friendly in the catalysis field.
Tuning effect of amorphous Fe2O3on Mn3O4for efficient atom-economic synthesis of imines at low temperature: Improving [O] transfer cycle of Mn3+/Mn2+in Mn3O4
Cao, Xiao,Gou, Galian,Long, Yu,Luo, Shicheng,Luo, Yutong,Ma, Jiantai,Qin, Jiaheng,Wang, Kaizhi,Wu, Wei
, p. 5628 - 5640 (2020/09/17)
A facile and scaled-up synthesis route to efficient and environment-friendly metal oxide catalysts with desirable properties is of great practical importance, owing to their excellent performance as heterogeneous catalysts in organic synthesis. Herein, a novel amorphous Fe2O3 modified Mn3O4 catalyst (Fe5Mn5-100) has been prepared by adopting a simple co-precipitation method following low temperature baking. Fe5Mn5-100 showed exceptionally high catalytic activity for the atom-economic production of imine from benzyl alcohol with aniline, giving a 98% imine yield at 60 °C in only 3 h, which is higher than all of the reported non-noble and noble metal catalysts. Importantly, Fe5Mn5-100 could still exhibit extraordinary catalytic performance on a large-scale reaction without any solvent, including the frequently used toxic mesitylene, xylene or toluene. Interestingly, the amorphous Fe2O3-100 provided no catalytic activity, and pure Mn3O4-100 showed very inferior catalytic activity towards this reaction. Further detailed characterizations and experimental results revealed that amorphous Fe2O3 plays an important role in expediting the [O] transfer cycle of Mn3+/Mn2+ in Mn3O4, and enhances the oxidation ability and acidity of Fe5Mn5-100. This discovery would provide a new avenue for the atom-economic and environment-friendly industrial synthesis of imine. This journal is
Unlocking the direct photocatalytic difluoromethylation of CN bonds
Alemán, José,Garrido-Castro, Alberto F.,Gini, Andrea,Maestro, M. Carmen
supporting information, p. 3769 - 3772 (2020/04/10)
The current study presents a direct CF2H radical addition to CN bonds predicated on the photocatalytic activation of commercially available zinc difluoromethanesulfinate. The mild conditions in place lead to impressive structural diversity, as quinoxalinones and dibenzazepines, among others, are successfully functionalized.
