5981-33-9Relevant academic research and scientific papers
Mimicking transition metals in borrowing hydrogen from alcohols
Banik, Ananya,Ahmed, Jasimuddin,Sil, Swagata,Mandal, Swadhin K.
, p. 8353 - 8361 (2021/07/02)
Borrowing hydrogen from alcohols, storing it on a catalyst and subsequent transfer of the hydrogen from the catalyst to anin situgenerated imine is the hallmark of a transition metal mediated catalyticN-alkylation of amines. However, such a borrowing hydrogen mechanism with a transition metal free catalytic system which stores hydrogen molecules in the catalyst backbone is yet to be established. Herein, we demonstrate that a phenalenyl ligand can imitate the role of transition metals in storing and transferring hydrogen molecules leading to borrowing hydrogen mediated alkylation of anilines by alcohols including a wide range of substrate scope. A close inspection of the mechanistic pathway by characterizing several intermediates through various spectroscopic techniques, deuterium labelling experiments, and DFT study concluded that the phenalenyl radical based backbone sequentially adds H+, H˙ and an electron through a dearomatization process which are subsequently used as reducing equivalents to the C-N double bond in a catalytic fashion.
Silicon hydrogenation reaction method of organic boron and inorganic alkali catalysis amide (by machine translation)
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Paragraph 0107-0113; 0126-0129, (2020/08/18)
The method is characterized in that organic boron and inorganic bases are used as catalysts, silane is used as a reducing agent, primary amide is reduced to primary amine or dehydration dinitrile, the secondary amide is reduced to a secondary amine or aldimine, and the tertiary amide is reduced to tertiary amine. The method has the advantages of simple operation, mild reaction conditions, wide substrate universality, good functional group compatibility and the like, and has the characteristics of good stability, cheap and accessible catalyst, simple and convenient operation, high practicality and the like. (by machine translation)
Synthesis, characterization and mixed micellization study of benzene sulphonate based gemini surfactant with sodium dodecyl sulphate
Wani, Farooq Ahmad,Khan, Abbul Bashar,Alshehri, Abdulmohsen Ali,Malik, Maqsood Ahmad,Ahmad, Rabia,Patel, Rajan
, p. 270 - 278 (2019/04/29)
Herein, we have shown the mixed micelle formation between anionic benzene sulphonate (viz., sodium 4,4′-(16,25-dioxo-15,17,24,26-tetraaza-hexatriacontane15,26-diyl)dibenzenesulphonate [BSC14-C6-14CSB]and sodium 4,4′-(18,27-dioxo-17,19,26,28-tetraaza-tetracontane15,26-diyl)dibenzenesulphonate [BSC16-C6-16CSB])with conventional anionic surfactant (sodium dodecyl sulphate [SDS])by conductivity and fluorometry methods. The conductivity measurements were done over a range of mole fractions of SDS at different temperatures to study the mixed micellization and thermodynamic parameters, while fluorescence measurements were performed over entire range of mole fraction of SDS in order to observe the aggregation and micro-polarity. The conductometric study confirms the synergism in all mole fractions of SDS with [BSC14-C6-14CSB]and [BSC16-C6-16CSB]at all temperatures. The Rubinghs regular solution theory (RST)was employed to evaluate micellar mole fraction, X1, ideal micellar mole fraction, Xideal, interaction parameter (β), activity coefficients (f1, and f2)for both mixed micelles systems and Gibbs excess free energy (GE). The GE values are negative for entire mole fraction range suggesting the formation of stable mixed micelles. In addition to this, other thermodynamic parameters like Gibbs free energy change of micellization (ΔGmic), enthalpy change of micellization (ΔHmic)and entropy change of micellization (ΔSmic)were evaluated. Also, the aggregation number (Nagg)in micelles was calculated using pyrene probe fluorescence measurement. The binding constant, dielectric constant and micropolarity of mixed systems of SDS + [BSC14-C6-14CSB]and SDS + [BSC16-C6-16CSB]binary mixtures were obtained from the ratio of peak strength (I1/I3)from the pyrene probe fluorescence emission spectra.
A BEt3-Base catalyst for amide reduction with silane
Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
, (2019/05/22)
Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.
Efficient nickel-catalysed: N -alkylation of amines with alcohols
Afanasenko, Anastasiia,Elangovan, Saravanakumar,Stuart, Marc C. A.,Bonura, Giuseppe,Frusteri, Francesco,Barta, Katalin
, p. 5498 - 5505 (2018/11/20)
The selective N-alkylation of amines with alcohols via the borrowing hydrogen strategy represents a prominent sustainable catalytic method, which produces water as the only by-product and is ideally suited for the catalytic transformation of widely available alcohol reaction partners that can be derived from renewable resources. Intensive research has been devoted to the development of novel catalysts that are mainly based on expensive noble metals. However, the availability of homogeneous or heterogeneous non-precious metal catalysts for this transformation is very limited. Herein we present a highly active and remarkably easy-to-prepare Ni based catalyst system for the selective N-alkylation of amines with alcohols, that is in situ generated from Ni(COD)2 and KOH under ligand-free conditions. This novel method is very efficient for the functionalization of aniline and derivatives with a wide range of aromatic and aliphatic alcohols as well as diols and exhibits excellent functional group tolerance including halides, benzodioxane and heteroaromatic groups. Several TEM measurements combined with elemental analysis were conducted in order to gain insight into the nature of the active catalyst and factors influencing reactivity.
Cobalt-Rhodium Heterobimetallic Nanoparticle-Catalyzed N-Alkylation of Amines with Alcohols to Secondary and Tertiary Amines
Chung, Hyunho,Chung, Young Keun
, p. 8533 - 8542 (2018/07/30)
Without the requirement for base or other additives, Co2Rh2/C can selectively catalyze both mono- and bis-N-alkylation through the coupling of simple alcohols with amines, yielding a range of secondary and tertiary amines in good to excellent isolated yields. The reaction can be applied to benzyl alcohol with optically active 1-phenylethan-1-amines, and secondary amines were isolated in quantitative yields with an excellent enantiomeric excess (ee > 94%). Selectivity is achieved by varying the reaction temperature and amount of catalyst used. This catalytic system has several advantages including eco-friendliness and a simple workup procedure. The catalyst can be successfully recovered and reused ten times without any significant loss of activity.
Rhenium-Loaded TiO2: A Highly Versatile and Chemoselective Catalyst for the Hydrogenation of Carboxylic Acid Derivatives and the N-Methylation of Amines Using H2 and CO2
Toyao, Takashi,Siddiki,Morita, Yoshitsugu,Kamachi, Takashi,Touchy, Abeda S.,Onodera, Wataru,Kon, Kenichi,Furukawa, Shinya,Ariga, Hiroko,Asakura, Kiyotaka,Yoshizawa, Kazunari,Shimizu, Ken-Ichi
supporting information, p. 14848 - 14859 (2017/10/27)
Herein, we report a heterogeneous TiO2-supported Re catalyst (Re/TiO2) that promotes various selective hydrogenation reactions, which includes the hydrogenation of esters to alcohols, the hydrogenation of amides to amines, and the N-methylation of amines, by using H2 and CO2. Initially, Re/TiO2 was evaluated in the context of the selective hydrogenation of 3-phenylpropionic acid methyl ester to afford 3-phenylpropanol (pH2 =5 MPa, =5 MPa, T=180 °C), which revealed a superior performance over other catalysts that we tested in this study. In contrast to other typical heterogeneous catalysts, hydrogenation reactions with Re/TiO2 did not produce dearomatized byproducts. DFT studies suggested that the high selectivity for the formation of alcohols in favor of the hydrogenation of aromatic rings is ascribed to the higher affinity of Re towards the COOCH3 group than to the benzene ring. Moreover, Re/TiO2 showed a wide substrate scope for the hydrogenation reaction (19 examples). Subsequently, this Re/TiO2 catalyst was applied to the hydrogenation of amides, the N-methylation of amines, and the N-alkylation of amines with carboxylic acids or esters.
