4439-56-9Relevant academic research and scientific papers
Furfural and 5-(hydroxymethyl)furfural valorization using homogeneous Ni(0) and Ni(II) catalysts by transfer hydrogenation
Arévalo, Alma,García, Juventino J.,Jurado-Vázquez, Tamara
supporting information, (2021/11/27)
The complex [dippeNi(COD)] (dippe =1,2-bis(diisopropyl phosphino)ethane) was used as a catalytic precursor in furfural (FF) and 5-(hydroxymethyl)furfural (HMF) valorization, along with formic acid as hydrogen transfer agent, to produce the corresponding a
Reusable Co-nanoparticles for general and selectiveN-alkylation of amines and ammonia with alcohols
Beller, Matthias,Gawande, Manoj B.,Jagadeesh, Rajenahally V.,Kadam, Ravishankar G.,Li, Xinmin,Ma, Zhuang,Petr, Martin,Zbo?il, Radek,Zhou, Bei
, p. 111 - 117 (2022/01/06)
A general cobalt-catalyzedN-alkylation of amines with alcohols by borrowing hydrogen methodology to prepare different kinds of amines is reported. The optimal catalyst for this transformation is prepared by pyrolysis of a specific templated material, which is generatedin situby mixing cobalt salts, nitrogen ligands and colloidal silica, and subsequent removal of silica. Applying this novel Co-nanoparticle-based material, >100 primary, secondary, and tertiary amines includingN-methylamines and selected drug molecules were conveniently prepared starting from inexpensive and easily accessible alcohols and amines or ammonia.
BF3·Et2O as a metal-free catalyst for direct reductive amination of aldehydes with amines using formic acid as a reductant
Fan, Qing-Hua,Liu, Xintong,Luo, Zhenli,Pan, Yixiao,Xu, Lijin,Yang, Ji,Yao, Zhen,Zhang, Xin
supporting information, p. 5205 - 5211 (2021/07/29)
A versatile metal- and base-free direct reductive amination of aldehydes with amines using formic acid as a reductant under the catalysis of inexpensive BF3·Et2O has been developed. A wide range of primary and secondary amines and diversely substituted aldehydes are compatible with this transformation, allowing facile access to various secondary and tertiary amines in high yields with wide functional group tolerance. Moreover, the method is convenient for the late-stage functionalization of bioactive compounds and preparation of commercialized drug molecules and biologically relevant N-heterocycles. The procedure has the advantages of simple operation and workup and easy scale-up, and does not require dry conditions, an inert atmosphere or a water scavenger. Mechanistic studies reveal the involvement of imine activation by BF3and hydride transfer from formic acid.
Continuous flow heterogeneous catalytic reductive aminations under aqueous micellar conditions enabled by an oscillatory plug flow reactor
?tv?s, Sándor B.,Buchholcz, Balázs,Darvas, Ferenc,Kappe, C. Oliver,Novák, Zoltán,Sipos, Gellért,Wernik, Michaela
supporting information, p. 5625 - 5632 (2021/08/16)
Despite the fact that continuous flow processing exhibits well-established technical advances, aqueous micellar chemistry, a field that has proven extremely useful in shifting organic synthesis to sustainable water-based media, has mostly been explored under conventional batch-based conditions. This is particularly because of the fact that the reliable handling of slurries and suspensions in flow has been considered as a significant technical challenge. Herein, we demonstrate that the strategic application of an oscillatory plug flow reactor enables heterogeneous catalytic reductive aminations in aqueous micellar media enhancing mass transport and facilitating process simplicity, stability and scalability. The micellar flow process enabled a broad range of substrates, including amino acid derivatives, to be successfully transformed under reasonably mild conditions utilizing only very low amounts of Pd/C as a readily available heterogeneous catalyst. The preparative capabilities of the process along with the recyclability of the heterogenous catalyst and the aqueous reaction media were also demonstrated. This journal is
Palladium supported on magnesium hydroxyl fluoride: An effective acid catalyst for the hydrogenation of imines and N-heterocycles
Agbossou-Niedercorn, Francine,Corre, Yann,Dongare, Mohan K.,Kemnitz, Erhard,Kokane, Reshma,Michon, Christophe,Umbarkar, Shubhangi B.
supporting information, p. 19572 - 19583 (2021/11/04)
Palladium catalysts supported on acidic fluorinated magnesium hydroxide Pd/MgF2-x(OH)x were prepared through precipitation or impregnation methods. Applications to the hydrogenation of various aldimines and ketimines resulted in good catalytic activities at mild temperatures using one atmosphere of hydrogen. Quinolines, pyridines and other N-heterocycles were successfully hydrogenated at higher temperature and hydrogen pressure using low palladium loadings and without the use of any acid additive. Such reactivity trend confirmed the positive effect of the Br?nsted and Lewis acid sites from the fluorinated magnesium hydroxide support resulting in the effective pre-activation of N-heterocycle substrates and therefore in the good catalytic activity of the palladium nanoparticles during the hydrogenations. As demonstrated in the hydrogenation of imines, the catalyst was recycled up to 10 times without either loss of activity or palladium leaching. This journal is
Synthesis of an Fe-Pd bimetallic catalyst for: N -alkylation of amines with alcohols via a hydrogen auto-transfer methodology
Wu, Peng-Yu,Lu, Guo-Ping,Cai, Chun
, p. 396 - 404 (2021/01/28)
Hydrogen auto-transfer (HAT) or borrowing hydrogen (BH) methodology which combines dehydrogenation, intermediate reaction and hydrogenation, is recognized as an excellent strategy for one-pot synthesis from an economic and environmental point of view. Although much effort has been made on the development of catalysts for HAT reactions, harsh conditions, external base or large amounts of noble metals are still required in most reported catalysis systems, and thus the exploration of a highly efficient and recyclable heterogeneous catalyst remains meaningful. In this work, a novel bimetallic catalyst, Fe10Pd1/NC500 derived from bimetallic MOF NH2-MIL-101(Fe10Pd1), has been prepared, and the catalyst exhibits superior catalytic performance for the N-alkylation of amines with alcohols via a hydrogen auto-transfer methodology. High yields of the desired products were achieved at 120 °C with an alcohol/amine molar ratio of 2?:?1 and required no external additive or solvent. A distinct enhancement in catalytic performance is observed when compared with monometallic catalysts, which can be ascribed to the "synergistic effects"inside the bimetallic alloys. The N-doped carbon support has been revealed to provide the necessary basicity which avoids the requirement of an external base. Moreover, a wide substrate range and remarkable reusability have been shown by Fe10Pd1/NC500, and this work highlights new possibilities for bimetallic catalysts applied in sustainable chemistry.
Silver/manganese dioxide nanorod catalyzed hydrogen-borrowing reactions and tert-butyl ester synthesis
Luo, Huanhuan,Wang, Dawei,Xu, Zhaojun,Yang, Bobin,Yang, Yike
, p. 708 - 715 (2021/03/03)
Silver/manganese dioxide (Ag@MnO2) nanorods are synthesized and characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. It was discovered that Ag@MnO2 nanorods can realize hydrogen-borrowing reactions in high yields and are also effective for the synthesis of tert-butyl esters from aryl cyanides and tert-butyl hydroperoxide in a short period of time. Mechanistic experiments revealed that this catalytic system acts as a Lewis acid in hydrogen-borrowing reactions, while the synthesis of tert-butyl esters occurs through a radical pathway. This is the first report on the excellent catalytic activity of Ag@MnO2 nanorods as a catalyst.
Ruthenium(ii) complexes with N-heterocyclic carbene-phosphine ligands for theN-alkylation of amines with alcohols
Huang, Ming,Li, Yinwu,Lan, Xiao-Bing,Liu, Jiahao,Zhao, Cunyuan,Liu, Yan,Ke, Zhuofeng
supporting information, p. 3451 - 3461 (2021/05/03)
Metal hydride complexes are key intermediates forN-alkylation of amines with alcohols by the borrowing hydrogen/hydrogen autotransfer (BH/HA) strategy. Reactivity tuning of metal hydride complexes could adjust the dehydrogenation of alcohols and the hydrogenation of imines. Herein we report ruthenium(ii) complexes with hetero-bidentate N-heterocyclic carbene (NHC)-phosphine ligands, which realize smart pathway selection in theN-alkylated reactionviareactivity tuning of [Ru-H] species by hetero-bidentate ligands. In particular, complex6cbwith a phenyl wingtip group and BArF?counter anion, is shown to be one of the most efficient pre-catalysts for this transformation (temperature is as low as 70 °C, neat conditions and catalyst loading is as low as 0.25 mol%). A large variety of (hetero)aromatic amines and primary alcohols were efficiently converted into mono-N-alkylated amines in good to excellent isolated yields. Notably, aliphatic amines, challenging methanol and diamines could also be transformed into the desired products. Detailed control experiments and density functional theory (DFT) calculations provide insights to understand the mechanism and the smart pathway selectionvia[Ru-H] species in this process.
Ru(II)-NHC catalysed N-Alkylation of amines with alcohols under solvent-free conditions
Karaca, Emine ?zge,Dehimat, Zieneb Imene,Ya?ar, Sedat,Gürbüz, Nevin,Tebbani, Dahmane,?etinkaya, Bekir,?zdemir, ?smail
, (2021/04/02)
The reaction of [RuCl2(p-cymene)]2 with in situ prepared Ag-N-heterocyclic carbene (NHC) complexes yields a series of [RuCl2(p-cymene)(NHC)] complexes (2). All of the complexes have been characterised by elemental analysis, and 1H NMR and 13C NMR spectroscopies. These complexes have been tested for the N-alkylation of aromatic amines with arylmethyl alcohols under neat conditions in the presence of KOtBu at 120 °C. Compounds (2) are stable and have high catalytic/selective activity for the N-alkylation reactions of primary amines to afford secondary amines.
Half-sandwich Ru(ii) arene complexes bearing benzimidazole ligands for theN-alkylation reaction of aniline with alcohols in a solvent-free medium
?i?ek, Metin,Gürbüz, Nevin,?zdemir, Nam?k,?zdemir, ?smail,?spir, Esin
, p. 11075 - 11085 (2021/07/02)
In this article, the directN-alkylation reactions of amines with alcohol derivatives using the borrowing hydrogen methodology have been investigated. For this purpose, a new series of half-sandwich ruthenium(ii) complexes bearing N-coordinated benzimidazole complexes have been synthesized and fully characterized by FT-IR,1H NMR and13C NMR spectroscopies. Additionally, the structures of the complexes2a-2ehave been characterized by X-ray crystallography. All new complexes were investigated for their catalytic activities in the alkylation reaction of amines with alcohol derivatives. It was found that alkylation reactions in a solvent-free medium are efficient and selective.
