95-00-1Relevant academic research and scientific papers
Reaction of Diisobutylaluminum Borohydride, a Binary Hydride, with Selected Organic Compounds Containing Representative Functional Groups
Amberchan, Gabriella,Snelling, Rachel A.,Moya, Enrique,Landi, Madison,Lutz, Kyle,Gatihi, Roxanne,Singaram, Bakthan
supporting information, p. 6207 - 6227 (2021/05/06)
The binary hydride, diisobutylaluminum borohydride [(iBu)2AlBH4], synthesized from diisobutylaluminum hydride (DIBAL) and borane dimethyl sulfide (BMS) has shown great potential in reducing a variety of organic functional groups. This unique binary hydride, (iBu)2AlBH4, is readily synthesized, versatile, and simple to use. Aldehydes, ketones, esters, and epoxides are reduced very fast to the corresponding alcohols in essentially quantitative yields. This binary hydride can reduce tertiary amides rapidly to the corresponding amines at 25 °C in an efficient manner. Furthermore, nitriles are converted into the corresponding amines in essentially quantitative yields. These reactions occur under ambient conditions and are completed in an hour or less. The reduction products are isolated through a simple acid-base extraction and without the use of column chromatography. Further investigation showed that (iBu)2AlBH4 has the potential to be a selective hydride donor as shown through a series of competitive reactions. Similarities and differences between (iBu)2AlBH4, DIBAL, and BMS are discussed.
PROCESS FOR PREPARATION OF HALOGENATED BENZYLAMINE AND INTERMEDIATES THEROF
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Page/Page column 20, (2020/08/13)
The present invention provides an improved process for the preparation of halogenated benzylamine having the formula I from halogenated benzonitriles, Formula I wherein, X1 is selected from group consisting of hydrogen, chloro or fluoro, provided atleast one X1 is chloro or fluoro.
Nano-Fe3O4@SiO2-SO3H: A magnetic, reusable solid-acid catalyst for solvent-free reduction of oximes to amines with the NaBH3CN/ZrCl4 system
Sadighnia, Leila,Zeynizadeh, Behzad,Karami, Shiva,Abdollahi, Mohammad
, p. 535 - 542 (2019/01/04)
In this study, the immobilization of sulfonic acid on silica-layered magnetite was carried out by the reaction of ClSO3H with silica-layered magnetite. The prepared magnetic nanoparticles of Fe3O4@SiO2-SO3H were then characterized using scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometry, and transmission electron microscopy. The sulfonated nanocomposite exhibited excellent catalytic activity and reusability in the reduction of various aldoximes and ketoximes with NaBH3CN in the presence of ZrCl4. All reactions were carried out under solvent-free conditions (r.t. or 75–80°C) within 3–70 min to afford amines in high to excellent yields.
Green and convenient protocols for the efficient reduction of nitriles and nitro compounds to corresponding amines with NaBH4 in water catalyzed by magnetically retrievable CuFe2O4 nanoparticles
Zeynizadeh, Behzad,Mohammad Aminzadeh, Farkhondeh,Mousavi, Hossein
, (2019/03/23)
Abstract: In this study, firstly, CuFe2O4 nanoparticles were prepared by a simple operation. The structure of the mentioned nanoparticles was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, inductively coupled plasma-optical emission spectrometry, vibrating sample magnetometer and also Brunauer–Emmett–Teller and Barrett–Joyner–Halenda analyses. The prepared magnetically copper ferrite nanocomposite was successfully applied as a simple, cost-effective, practicable, and recoverable catalyst on the green, highly efficient, fast, base-free, and ligand-free reduction of nitriles and also on the affordable and eco-friendly reduction of nitro compounds with the broad substrate scope to the corresponding amines with NaBH4 in water at reflux in high to excellent yields. Graphical abstract: [Figure not available: see fulltext.].
Synthesis and characterization of copper nanoparticles on walnut shell for catalytic reduction and C-C coupling reaction
Zamani, Asghar,Poursattar Marjani, Ahmad,Nikoo, Abbas,Heidarpour, Mojtaba,Dehghan, Ahmad
, p. 176 - 181 (2018/09/25)
Walnut shell-stabilized copper nanoparticles (CuNP/WS) were successfully prepared by a simple reaction of copper sulfate and Sodium borohydride. Formation of copper nanoparticles in this bio-nanocomposite was observed by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscope (EDX). CuNP/WS was found to be an efficient, inexpensive, easy to prepare, green and reusable catalyst in the reduction of aromatic nitro and nitrile compounds to their corresponding amines with NaBH4 at 35 °C in aqueous medium. We continued our studies on the application of this nanocomposite in the classic Ullman reaction to synthesize biaryl. This method has the advantages of high yields, elimination of expensive stabilizer and homogeneous catalysts, simple methodology and easy work up. The catalyst can be recovered from the reaction mixture and reused several times without any significant loss of catalytic activity.
The efficient solvent-free reduction of oximes to amines with NaBH3CN catalyzed by ZrCl4/nano Fe3O4 system
Sadighnia, Leila,Zeynizadeh, Behzad
, p. 873 - 878 (2015/03/18)
Reduction of various aldoximes and ketoximes to the corresponding amines was carried out easily and efficiently with NaBH3CN in the presence of ZrCl4/nano Fe3O4 system. The reactions were carried out under solvent-free conditions at room temperature or 75-80°C to afford amines in high to excellent yields.
Fe3O4-SiO2-P4VP pH-sensitive microgel for immobilization of nickel nanoparticles: An efficient heterogeneous catalyst for nitrile reduction in water
Nabid, Mohammad Reza,Bide, Yasamin,Niknezhad, Mahvash
, p. 538 - 546 (2014/03/21)
Fe3O4 magnetic nanoparticles (MNPs) were modified with (3-aminopropyl)triethoxysilane through silanization. An atom transfer radical polymerization-initiating site immobilized onto amine-functionalized Fe3O4 MNPs. The surface-initiated atom transfer radical polymerization of 4-vinylpyridine was then performed in the presence of Fe 3O4-SiO2-Br nanoparticles, which led to the formation of Fe3O4-SiO2-P4VP [P4VP=poly(4-vinylpyridine)] hybrid microgels cross-linked with Fe 3O4 MNPs. Our approach uses polymer microgels as templates for the synthesis of nickel nanoparticles (NiNPs). The tunable properties of synthesized NiNPs@Fe3O4-SiO2-P4VP pH-sensitive microgels were used in the catalytic reduction of aliphatic and aromatic nitriles. Moreover, the catalytic activity of metal nanocomposites that can be modulated by the volume transition of microgel structures with changing pH has been evaluated. TEM, X-ray photoelectron spectroscopy, thermogravimetric analysis, atomic absorption spectroscopy, XRD, UV/Vis spectroscopy, and FTIR spectroscopy were used to characterize the resultant catalyst. Mystery solved: Our approach uses polymer microgels as templates for the synthesis of nickel nanoparticles. The tunable properties of synthesized NiNPs@Fe3O 4-SiO2-P4VP [NiNPs=nickel nanoparticles; P4VP=poly(4-vinylpyridine)] pH-sensitive microgels are used in the catalytic reduction of aliphatic and aromatic nitriles. Moreover, the catalytic activity of metal nanocomposites that can be modulated by the volume transition of microgel structures with changing pH has been evaluated. Copyright
A new and convenient method for reduction of oximes to amines with NaBH3CN in the presence of MoCl5/NaHSO4? H2O system
Kouhkan, Mehri,Zeynizadeh, Behzad
experimental part, p. 3323 - 3326 (2012/02/04)
Various aldoximes and ketoximes were efficiently reduced to their corresponding amines with NaBH3CN in the presence of MoCl 5/NaHSO4?H2O system. Reduction reactions were carried out in refluxing EtOH or DMF within 0.3-3.8 h to afford the amines in high to excellent yields.
A rapid and practical protocol for solvent-free reduction of oximes to amines with NaBH4/ZrCl4/Al2O3 system
Zeynizadeh, Behzad,Kouhkan, Mehri
experimental part, p. 3448 - 3452 (2012/02/01)
Solvent-free reduction of various aldoximes and ketoximes to the corresponding amines was performed easily and efficiently with NaBH4 in the presence of ZrCl4 supported on Al2O3. The reactions were carried out rapidly (within 2 min) at room temperature to afford the amines in high to excellent yields.
Reductions of aliphatic and aromatic nitriles to primary amines with diisopropylaminoborane
Haddenham, Dustin,Pasumansky, Lubov,DeSoto, Jamie,Eagon, Scott,Singaram, Bakthan
experimental part, p. 1964 - 1970 (2009/07/01)
Diisopropylaminoborane [BH2Nf)Pr)2] in the presence of a catalytic amount of lithium borohydride (LiBH4) reduces a large variety of aliphatic and aromatic nitriles in excellent yields. BH 2NOPr)2 can be prepared by two methods: first by reacting diisopropylamineborane [(iPr)2N)BH3] with 1.1 equiv of n-butylhthium (n-BuLi) followed by methyl iodide (MeI), or reacting iPrN:BH 3 with 1 equiv of n-BuLi followed by trimethylsilyl chloride (TMSCl). BH2N(ZPr)2 prepared with MeI was found to reduce benzonitriles to the corresponding benzylamines at ambient temperatures, whereas diisopropylaminoborane prepared with TMSCl does not reduce nitriles unless a catalytic amount of a lithium ion source, such as LiBH4 or lithium tetraphenylborate (LiBPh4), is added to the reaction. The reductions of benzonitriles with one or more electron-withdrawing groups on the aromatic ring generally occur much faster with higher yields. For example, 2,4-dichlorobenzonitrile was successfully reduced to 2,4-dichlorobenzylamine in 99% yield after 5 h at 25 °C. On the other hand, benzonitriles containing electron-donating groups on the aromatic ring require refluxing in tetrahydrofuran (THF) for complete reduction. For instance, 4- methoxybenzonitrile was successfully reduced to 4-methoxybenzylamine in 80% yield. Aliphatic nitriles can also be reduced by the BH2N(iPr) 2/cat. LiBH4 reducing system. Benzyl cyanide was reduced to phenethylamine in 83% yield. BH2NOPr)2 can also reduce nitriles in the presence of unconjugated alkenes and alkynes such as the reduction of 2-hexynenitrile to hex-5-yn-l-amine in 80% yield. Unfortunately, selective reduction of a nitrile in the presence of an aldehyde is not possible as aldehydes are reduced along with the nitrile. However, selective reduction of the nitrile group at 25 °C in the presence of an ester is possible as long as the nitrile group is activated by an electron-withdrawing substituent. It should be pointed out that lithium aminoborohydrides (LABs) do not reduce nitriles under ambient conditions and behave as bases with aliphatic nitriles as well as nitriles containing acidic a-protons. Consequently, both LABs and BH2NOPr)2 are complementary to each other and offer methods for the selective reductions of multifunctional compounds.
