17494-29-0Relevant articles and documents
Carbon monoxide-driven osmium catalyzed reductive amination harvesting WGSR power
Afanasyev, Oleg I.,Biriukov, Klim O.,Chusov, Denis,Godovikova, Maria,Loginov, Dmitry A.,Nelyubina, Yulia V.,Tsygankov, Alexey A.,Vasilyev, Dmitry V.,Vinogradov, Mikhail M.
, p. 4922 - 4930 (2021/07/26)
Herein, we present the first example of Os-catalyzed efficient reductive amination under water-gas shift reaction conditions. The developed catalytic systems are formedin situin aqueous solutions, employ as small as 0.0625 mol% osmium and are capable of delivering reductive amination products for a broad range of aliphatic and aromatic carbonyl compounds and amines. The scope of the reaction, active catalytic systems, possible limitations of the method and DFT-supported mechanistic considerations are discussed in detail in the manuscript.
Phosphine ligands in the ruthenium-catalyzed reductive amination without an external hydrogen source
Makarova, Maria,Afanasyev, Oleg I.,Kliuev, Fedor,Nelyubina, Yulia V.,Godovikova, Maria,Chusov, Denis
, (2021/04/15)
A systematic study of the phosphine additives influence on the activity of a ruthenium catalyst in reductive amination without an external hydrogen source was carried out. [CymeneRuCl2]2 was used as a reference catalyst, and a broad set of phosphines including Alk3P, Alk2ArP, Ar3P and X3P was screened. Three complexes of general formula (Cymene)RuCl2PR3 were isolated in a pure form, and their catalytic activity was compared with the in situ generated complexes. Nonhindered triarylphosphines with electron acceptor groups were found to be the most perspective activating agents, increasing the activity of the catalyst approx. six times, Alk2ArP ligands have less noticeable influence, while trialkylphosphines strongly deactivate the ruthenium catalyst.
Thioglycerol-Stabilized Rhodium Nanoparticles in Biphasic Medium as Catalysts in Multistep Reactions
Guerrero-Ríos, Itzel,Portales-Martínez, Benjamín,Reina, Antonio,Serrano-Maldonado, Alejandro
supporting information, (2020/07/04)
Small rhodium nanoparticles (ca. 3.5 nm) were prepared by the decomposition of an organometallic precursor under hydrogen pressure in glycerol using 1-thioglycerol as stabilizer. Full characterization in the solid state [HR-TEM, EDX, XPS] showed a fcc structure for the Rh0/RhI nanoparticles capped with thiolate ligand. Reduction of different functionalities, including nitro groups and imines, was applied to tandem reductive amination of aldehydes with primary and secondary amines, and to the synthesis of N-substituted anilines from nitrobenzene. In addition, thiolate-capped RhNPs could be recovered and reused up to 5 runs without loss of activity nor selectivity.
An Efficient Palladium-Catalysed Aminocarbonylation of Benzyl Chlorides
Oram, Niall,Richardson, Jeffery,Rilvin-Derrick, Eloise
, p. 369 - 372 (2020/02/27)
An improved procedure for the aminocarbonylation of benzyl chloride derivatives using carbon monoxide and either primary or secondary amines has been developed. Studying the competing background alkylation reaction allowed the solvent and base to be selected for a simple catalyst screen, which, in turn, enabled the discovery of a method for the preparation of 2-arylacetamides under mild conditions, with minimal side-products using an inexpensive phosphine ligand. This non-traditional optimisation strategy allowed us to overcome the background alkylation, which has been cited as justification for the development of more complex and less atom-economical approaches.
Hydrazone complexes of ruthenium(II): Synthesis, crystal structures and catalytic applications in N-alkylation reactions
Murugan, Kaliyappan,Natarajan, Karuppannan,Nirmala, Muthukumaran,Vijayapritha, Subbarayan,Viswanathamurthi, Periasamy
, (2020/07/21)
A series of new Ru(II) complexes of 8-hydroxy quinoline-2-carboxyaldehyde hydrazone of the general formula [RuH(CO)(EPh3)2L] (1–6) (E = P or As, L = N’-((8-hydroxyquinolin-2-yl)methylene)thiophene-2-carbohydrazide (HQ-THy), N’-((8-hydroxyquinolin-2-yl)methylene)isonicotinohydrazide (HQ-IHy), N’-((8-hydroxyquinolin-2-yl)methylene) benzohydrazide (HQ-BHy)) have been synthesized. They have been characterized by elemental analysis, IR, NMR (1H, 13C & 31P) and ESI-MS spectral methods. Further, structures of two of the complexes have been determined by single crystal X-ray diffraction technique which revealed a pseudo octahedral geometry with the coordination of the quinoline nitrogen and quinoline oxygen atoms of the ligand. All the new complexes have been employed as efficient catalysts in N-alkylation reactions for the synthesis of tertiary amines by the coupling of secondary amines with aromatic primary alcohols at low catalyst loading with maximum yields. In addition, the effects of substituents on the ligands, different solvents as well as bases and amounts of catalyst loading on the catalytic activity of the complexes have been thoroughly investigated. Complex 1 was found to be efficient catalyst towards N-alkylation of alcohols with the amine. Further, a variety of secondary amines and aromatic (hetero) primary alcohols with various functional groups have also been successfully used in the N-alkylation reactions and it has been found that only one equivalent of the alcohol was consumed in the process.
Photochemical benzylic bromination in continuous flow using BrCCl3 and its application to telescoped p-methoxybenzyl protection
Otake, Yuma,Williams, Jason D.,Rincón, Juan A.,De Frutos, Oscar,Mateos, Carlos,Kappe, C. Oliver
, p. 1384 - 1388 (2019/02/14)
BrCCl3 represents a rarely used benzylic brominating reagent with complementary reactivity to other reagents. Its reactivity has been revisited in continuous flow, revealing compatibility with electron-rich aromatic substrates. This has brought about the development of a p-methoxybenzyl bromide generator for PMB protection, which was successfully demonstrated on a pharmaceutically relevant intermediate on 11 g scale, giving 91% yield and a PMB-Br space-time-yield of 1.27 kg L?1 h?1
Controlled Reduction of Carboxamides to Alcohols or Amines by Zinc Hydrides
Ong, Derek Yiren,Yen, Zhihao,Yoshii, Asami,Revillo Imbernon, Julia,Takita, Ryo,Chiba, Shunsuke
supporting information, p. 4992 - 4997 (2019/03/13)
New protocols for controlled reduction of carboxamides to either alcohols or amines were established using a combination of sodium hydride (NaH) and zinc halides (ZnX2). Use of a different halide on ZnX2 dictates the selectivity, wherein the NaH-ZnI2 system delivers alcohols and NaH-ZnCl2 gives amines. Extensive mechanistic studies by experimental and theoretical approaches imply that polymeric zinc hydride (ZnH2)∞ is responsible for alcohol formation, whereas dimeric zinc chloride hydride (H?Zn?Cl)2 is the key species for the production of amines.
Fast continuous alcohol amination employing a hydrogen borrowing protocol
Labes, Ricardo,Mateos, Carlos,Battilocchio, Claudio,Chen, Yiding,Dingwall, Paul,Cumming, Graham R.,Rincón, Juan A.,Nieves-Remacha, Maria José,Ley, Steven V.
supporting information, p. 59 - 63 (2019/01/11)
A continuous flow method for the direct conversion of alcohols to amines via a hydrogen borrowing approach is reported. The method utilises a low loading (0.5%) of a commercial catalyst system ([Ru(p-cymene)Cl2]2 and DPEPhos), reagent grade solvent and is selective for primary alcohols. Successful methylation of amines using methanol and the direct dimethylamination of alcohols using commercial dimethylamine solution are reported. The synthesis of two pharmaceutical agents Piribedil (5) and Buspirone (25) were accomplished in good yields employing these new methods.
Alkylation of cyclic amines with alcohols catalyzed by Ru(II) complexes bearing N-Heterocyclic carbenes
Ulu, ?znur Do?an,Gürbüz, Nevin,?zdemir, ?smail
, p. 645 - 651 (2018/01/04)
This paper includes the synthesis of 2-(1,3-dioxane-2-yl)ethyl substituted benzimidazole substituted N-heterocyclic carbenes precursors and their ruthenium complexes. Synthesized compounds were characterized by elemental analysis and NMR spectroscopy. All complexes have been tested in the alkylation of pyrrolidine and morpholine with alcohols, showing an excellent activity in this reaction.
Selective, Catalytic, and Dual C(sp3)-H Oxidation of Piperazines and Morpholines under Transition-Metal-Free Conditions
Chamorro-Arenas, Delfino,Osorio-Nieto, Urbano,Quintero, Leticia,Hernández-García, Luís,Sartillo-Piscil, Fernando
, p. 15333 - 15346 (2019/01/03)
By using cheap and innocuous reagents, such as NaClO2, NaOCl, and catalytic amounts of TEMPO, a new environmentally friendly protocol for the selective and catalytic TEMPO C(sp3)-H oxidation of piperazines and morpholines to 2,3-diketopiperazines (2,3-DKP) and 3-morpholinones (3-MPs), respectively, has been developed. This novel direct access to 2,3-DKP from piperazines provides significant advantages over the traditional N-monoacylation/intramolecular C-N cyclization procedure. Additionally, by modulating the amounts of TEMPO, 2-alkoxyamino-3-morpholinone can be prepared from morpholine derivatives, which would enable further functionalization at the C2 position of the morpholine skeleton.
