4352-47-0Relevant academic research and scientific papers
Density Functional Theory and Quantum Theory of Atoms in Molecules Analysis: Influence of Intramolecular Interactions on Pirouetting Movement in Tetraalkylsuccinamide[2]rotaxanes
Martins, Marcos A. P.,Rodrigues, Leticia V.,Meyer, Alexandre R.,Frizzo, Clarissa P.,H?rner, Manfredo,Zanatta, Nilo,Bonacorso, Helio G.,Berná, Jose,Alajarín, Mateo
, p. 5845 - 5857 (2017)
The first Quantum Theory of Atoms in Molecules (QTAIM) analysis of [2]rotaxanes was used in combination with quantum mechanical calculations and variable temperature NMR experiments. The study shows all the intramolecular interactions of tetraalkylsuccinamide[2]rotaxanes with different templates. The threads have different stoppers [R1R2NC(O)-CH2CH2-C(O)NR2R1, in which R2/R1 = CH2cy-Hex/CH2Ph, i-Bu, Bu, and Pr]. The different threads used allowed us verify that the contact area between the submolecular components (CMcy···Thr) is closely correlated with the interaction energy (GMcy···Thr) in the [2]rotaxanes studied. Furthermore, the QTAIM data and quantum mechanical calculations confirmed that, in all of the compounds, the hydrogen bonds are responsible for most of the energy from the intramolecular interactions that follow the C-H···π and H···H interactions, independent of the thread used. In the liquid state, using NMR 1H some intramolecular interactions were observed, which is in agreement with the data obtained in the solid state, thus making possible a comparison between the energy data obtained via the quantum mechanical calculations and the molecular movements of the [2]rotaxanes in solution. Consequently, a new way of understanding the intramolecular interactions in [2]rotaxanes and the influence they have on the movement of molecular machines is presented.
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.
Trimethyl Borate-Catalyzed, Solvent-Free Reductive Amination
Ramachandran, P. Veeraraghavan,Choudhary, Shivani,Singh, Aman
, p. 4274 - 4280 (2021/03/09)
Solvent-free reductive amination of aldehydes and ketones with aliphatic and aromatic amines in high-to-excellent yields has been achieved with sub-stoichiometric trimethyl borate as promoter and ammonia borane as reductant.
Nickel Complexes Bearing N,N,O-Tridentate Salicylaldiminato Ligand: Efficient Catalysts for Imines Formation via Dehydrogenative Coupling of Primary Alcohols with Amines
Han, Zhangang,Hao, Zhiqiang,Lin, Jin,Lu, Guo-Liang,Zhang, Junhua,Zhang, Xiaoying
, p. 3843 - 3853 (2021/11/18)
Treatment of salicylaldiminato ligand L1H-L2H (L1H = 2,4-di-tert-butyl-6-((quinolin-8-ylimino)methyl)phenol; L2H = 2,4-di-tert-butyl-6-(((2-(diethylamino)ethyl)imino)methyl)phenol) with Ni(OAc)2·4H2O in refluxing ethanol afforded nickel complexes [(L1)Ni(OAc)] (1) and [(L2)Ni(OAc)] (2), respectively. Reaction of L3H (L3H = (2,4-di-tert-butyl-6-(((2-(pyridin-2-yl)ethyl)imino)methyl)phenol)) with Ni(OAc)2·4H2O in the presence of excess triethylanmine gave the dual ligands coordinated nickel complex [(L2)2Ni] (3). Complexes 1-3 were well characterized by high-resolution mass spectrometry, infrared spectroscopy, elemental analysis, and X-ray diffraction analysis. All the three Ni(II) complexes exhibited efficient activity and good selectivity in the acceptorless dehydrogenative coupling of alcohols and amines to produce imines and diimines. The present protocol provides an atom-economical and sustainable route for the synthesis of various imine derivatives by employing an earth-abundant nickel salt and easily prepared salicylaldiminato ligands.
Heterogeneous Ru/TiO2for hydroaminomethylation of olefins: multicomponent synthesis of amines
An, Jinghua,Gao, Zhuyan,Wang, Yehong,Zhang, Zhixin,Zhang, Jian,Li, Lu,Tang, Bo,Wang, Feng
supporting information, p. 2722 - 2728 (2021/04/21)
Synthesizing aminesviathe hydroaminomethylation (HAM) reaction of olefins, a multicomponent reaction, has been regarded as one of the most attractive methods compared with the traditional methods considering the atom economy and environmental friendliness. However, the use of homogeneous catalysts, complex ligands containing diphosphine or nitrogen, and base or acid additives has severely hampered the utilization of these methods. Herein, an efficient heterogeneous Ru/TiO2-catalyzed HAM reaction of olefins is developed without any additives. Various amines, including secondary and tertiary amines, can be successfully obtained from olefins including aromatic and aliphatic olefins. Systematic studies demonstrate the lower electron density of Ruδ+and the higher number of acid sites of Ru/TiO2, leading to the high HAM reaction activity of olefins. Most importantly, nitrobenzene derivatives can also be transformed to the corresponding products over Ru/TiO2in excellent yields.
Ru(II) complexes containing (2-(pyren-1-ylmethylene)hydrazinyl)benzothiazole: Synthesis, solid-state structure, computational study and catalysis in N-alkylation reactions
Murugan, Kaliyappan,Ojwach, Stephen O.,Saravanan, Kandasamy,Vijayan, Paranthaman,Vijayapritha, Subbarayan,Viswanathamurthi, Periasamy
, (2020/07/27)
Reactions of (2-(pyren-1-ylmethylene)hydrazinyl)benzothiazole (L) with ruthenium(II) prefabricated precursors [RuHCl(CO)(EPh3)3] and [RuH2(CO)(EPh3)3] (E = P or As) afforded new Ru(II) complexes [RuCl(CO)(EPh3)2(L)] and [RuH(CO)(EPh3)2(L)] (E = P or As) (1–4). All the Ru(II) complexes (1–4) were characterized by IR, NMR spectroscopies, ESI-mass spectrometry and elemental analyses. The solid-state structures of Ru(II) complexes (2 and 3) were established by single crystal X-ray analyses and revealed distorted octahedral geometries around the ruthenium(II) ion and mono anionic bidentate N^N coordination mode for hydrazine ligand. The Ru(II) complexes 2 and 3 were also analyzed using Hirshfeld surface analysis and DFT calculations. Moreover, all the complexes (1–4) were utilized in the N-alkylation reactions of amines using alcohol. Complex 3 was found to be highly active towards N-alkylation of different aromatic amines with alcohol.
Simple Metal-Free Direct Reductive Amination Using Hydrosilatrane to Form Secondary and Tertiary Amines
Varjosaari, Sami E.,Skrypai, Vladislav,Suating, Paolo,Hurley, Joseph J. M.,Lio, Ashley M. De,Gilbert, Thomas M.,Adler, Marc J.
supporting information, p. 1872 - 1878 (2017/06/09)
This work describes the use of cheap, safe, and easy-to-handle hydrosilatrane as the reductant in direct reductive amination reactions. This efficient method enables a facile, metal-free access to secondary and tertiary amines from a wide range of aldehydes and ketones, with the synthesis of tertiary amines requiring no additives at all. This reaction demonstrates excellent functional group tolerance, chemoselectivity, and scalability. (Figure presented.).
A segmented flow platform for on-demand medicinal chemistry and compound synthesis in oscillating droplets
Hwang, Ye-Jin,Coley, Connor W.,Abolhasani, Milad,Marzinzik, Andreas L.,Koch, Guido,Spanka, Carsten,Lehmann, Hansjoerg,Jensen, Klavs F.
, p. 6649 - 6652 (2017/07/10)
We report an automated flow chemistry platform that can efficiently perform a wide range of chemistries, including single/multi-phase and single/multi-step, with a reaction volume of just 14 μL. The breadth of compatible chemistries is successfully demonstrated and the desired products are characterized, isolated, and collected online by preparative HPLC/MS/ELSD.
Efficient and Selective Hydrosilylation of Secondary and Tertiary Amides Catalyzed by an Iridium(III) Metallacycle: Development and Mechanistic Investigation
Corre, Yann,Trivelli, Xavier,Capet, Frédéric,Djukic, Jean-Pierre,Agbossou-Niedercorn, Francine,Michon, Christophe
, p. 2009 - 2017 (2017/06/13)
Readily accessible cationic IrIII metallacycles catalyze efficiently the chemoselective hydrosilylation of tertiary and secondary amides to amines. The catalyst described herein operates at low loadings using inexpensive 1,1,3,3-tetramethyldisiloxane and allows fast reactions with high yields, selectivities, and turnover numbers. A transient iminium intermediate has been observed for the first time by using mass spectrometry, and the activation of the catalyst and the silane reagent have been studied by using DFT calculations. These fundamental insights support the present and future improvements of IrIII metallacycles through proper ligand modifications and enable further broad applications of catalysts based on metallacycles.
Nickel-Catalyzed Reduction of Secondary and Tertiary Amides
Simmons, Bryan J.,Hoffmann, Marie,Hwang, Jaeyeon,Jackl, Moritz K.,Garg, Neil K.
supporting information, p. 1910 - 1913 (2017/04/11)
The nickel-catalyzed reduction of secondary and tertiary amides to give amine products is reported. The transformation is tolerant of extensive variation with respect to the amide substrate, proceeds in the presence of esters and epimerizable stereocenters, and can be used to achieve the reduction of lactams. Moreover, this methodology provides a simple tactic for accessing medicinally relevant α-deuterated amines.
