6232-11-7Relevant academic research and scientific papers
Healable luminescent self-assembly supramolecular metallogels possessing lanthanide (Eu/Tb) dependent rheological and morphological properties
Martnez-Calvo, Miguel,Kotova, Oxana,M?bius, Matthias E.,Bell, Alan P.,McCabe, Thomas,Boland, John J.,Gunnlaugsson, Thorfinnur
, p. 1983 - 1992 (2015)
Herein we present the use of lanthanide directed self-assembly formation (Ln(III) = Eu(III), Tb(III)) in the generation of luminescent supramolecular polymers, that when swelled with methanol give rise to self-healing supramolecular gels. These were analyzed by using luminescent and 1H NMR titrations studies, allowing for the identification of the various species involved in the subsequent Ln(III)-gel formation. These highly luminescent gels could be mixed to give a variety of luminescent colors depending on their Eu(III):Tb(III) stoichiometric ratios. Imaging and rheological studies showed that these gels prepared using only Eu(III) or only Tb(III) have different morphological and rheological properties, that are also different from those determined upon forming gels by mixing of Eu(III) and Tb(III) gels. Hence, our results demonstrate for the first time the crucial role the lanthanide ions play in the supramolecular polymerization process, which is in principle a host-guest interaction, and consequently in the self-healing properties of the corresponding gels, which are dictated by the same host-guest interactions.
Hydrosilylative reduction of primary amides to primary amines catalyzed by a terminal [Ni-OH] complex
Pandey, Pragati,Bera, Jitendra K.
, p. 9204 - 9207 (2021/09/20)
A terminal [Ni-OH] complex1, supported by triflamide-functionalized NHC ligands, catalyzes the hydrosilylative reduction of a range of primary amides into primary amines in good to excellent yields under base-free conditions with key functional group tolerance. Catalyst1is also effective for the reduction of a variety of tertiary and secondary amides. In contrast to literature reports, the reactivity of1towards amide reduction follows an inverse trend,i.e., 1° amide > 3° amide > 2° amide. The reaction does not follow a usual dehydration pathway.
Development of a selective matrix metalloproteinase 13 (MMP-13) inhibitor for the treatment of Osteoarthritis
Bendele, Alison M.,Neelagiri, Madhavi,Neelagiri, Venugopal,Sucholeiki, Irving
, (2021/07/12)
Osteoarthritis (OA) is a chronic disorder that causes damage to the cartilage and surrounding tissues and is characterized by pain, stiffness, and loss of function. Current treatments for OA primarily involve providing only relief of symptoms but does not
Nitrile Synthesis by Aerobic Oxidation of Primary Amines and in situ Generated Imines from Aldehydes and Ammonium Salt with Grubbs Catalyst
Utsumi, Tatsuki,Noda, Kenta,Kawauchi, Daichi,Ueda, Hirofumi,Tokuyama, Hidetoshi
supporting information, p. 3583 - 3588 (2020/08/05)
Herein, a Grubbs-catalyzed route for the synthesis of nitriles via the aerobic oxidation of primary amines is reported. This reaction accommodates a variety of substrates, including simple primary amines, sterically hindered β,β-disubstituted amines, allylamine, benzylamines, and α-amino esters. Reaction compatibility with various functionalities is also noted, particularly with alkenes, alkynes, halogens, esters, silyl ethers, and free hydroxyl groups. The nitriles were also synthesized via the oxidation of imines generated from aldehydes and NH4OAc in situ. (Figure presented.).
Synthesis, Characterization, and Catalytic Reactivity of {CoNO}8PCP Pincer Complexes
Pecak, Jan,Eder, Wolfgang,St?ger, Berthold,Realista, Sara,Martinho, Paulo N.,Calhorda, Maria José,Linert, Wolfgang,Kirchner, Karl
, p. 2594 - 2601 (2020/06/22)
The reaction of coordinatively unsaturated Co(II) PCP pincer complexes with nitric oxide leads to the formation of new, air-stable, diamagnetic mono nitrosyl compounds. The synthesis and characterization of five- and four-coordinate Co(III) and Co(I) nitrosyl pincer complexes based on three different ligand scaffolds is described. Passing NO through a solution of [Co(PCPNMe-iPr)Cl], [Co(PCPO-iPr)Cl] or [Co(PCPCH2-iPr)Br] led to the formation of the low-spin complex [Co(PCP-iPr)(NO)X] with a strongly bent NO ligand. Treatment of the latter species with (X = Cl, Br) AgBF4 led to chloride abstraction and formation of cationic square-planar Co(I) complexes of the type [Co(PCP-iPr)(NO)]+ featuring a linear NO group. This reaction could be viewed as a formal two electron reduction of the metal center by the NO radical from Co(III) to Co(I), if NO is counted as NO+. Hence, these systems can be described as {CoNO}8 according to the Enemark-Feltham convention. X-ray structures, spectroscopic and electrochemical data of all nitrosyl complexes are presented. Preliminary studies show that [Co(PCPNMe-iPr)(NO)]+ catalyzes efficiently the reductive hydroboration of nitriles with pinacolborane (HBpin) forming an intermediate {CoNO}8 hydride species.
A State-of-the-Art Heterogeneous Catalyst for Efficient and General Nitrile Hydrogenation
Formenti, Dario,Mocci, Rita,Atia, Hanan,Dastgir, Sarim,Anwar, Muhammad,Bachmann, Stephan,Scalone, Michelangelo,Junge, Kathrin,Beller, Matthias
supporting information, p. 15589 - 15595 (2020/10/02)
Cobalt-doped hybrid materials consisting of metal oxides and carbon derived from chitin were prepared, characterized and tested for industrially relevant nitrile hydrogenations. The optimal catalyst supported onto MgO showed, after pyrolysis at 700 °C, magnesium oxide nanocubes decorated with carbon-enveloped Co nanoparticles. This special structure allows for the selective hydrogenation of diverse and demanding nitriles to the corresponding primary amines under mild conditions (e.g. 70 °C, 20 bar H2). The advantage of this novel catalytic material is showcased for industrially important substrates, including adipodinitrile, picolinonitrile, and fatty acid nitriles. Notably, the developed system outperformed all other tested commercial catalysts, for example, Raney Nickel and even noble-metal-based systems in these transformations.
A cobalt phosphide catalyst for the hydrogenation of nitriles
Jitsukawa, Koichiro,Mitsudome, Takato,Mizugaki, Tomoo,Nakata, Ayako,Sheng, Min,Yamasaki, Jun
, p. 6682 - 6689 (2020/08/24)
The study of metal phosphide catalysts for organic synthesis is rare. We present, for the first time, a well-defined nano-cobalt phosphide (nano-Co2P) that can serve as a new class of catalysts for the hydrogenation of nitriles to primary amines. While earth-abundant metal catalysts for nitrile hydrogenation generally suffer from air-instability (pyrophoricity), low activity and the need for harsh reaction conditions, nano-Co2P shows both air-stability and remarkably high activity for the hydrogenation of valeronitrile with an excellent turnover number exceeding 58000, which is over 20- to 500-fold greater than that of those previously reported. Moreover, nano-Co2P efficiently promotes the hydrogenation of a wide range of nitriles, which include di- and tetra-nitriles, to the corresponding primary amines even under just 1 bar of H2 pressure, far milder than the conventional reaction conditions. Detailed spectroscopic studies reveal that the high performance of nano-Co2P is attributed to its air-stable metallic nature and the increase of the d-electron density of Co near the Fermi level by the phosphidation of Co, which thus leads to the accelerated activation of both nitrile and H2. Such a phosphidation provides a promising method for the design of an advanced catalyst with high activity and stability in highly efficient and environmentally benign hydrogenations. This journal is
HDAC INHIBITORS AND USES THEREOF
-
, (2019/09/30)
The present invention relates to histone deacetylase inhibitors, and to pharmaceutical compositions comprising the compounds, useful for the treatment of ischemia-reperfusion injury and for cardioprotection.
Catalytic Staudinger Reduction at Room Temperature
Lenstra, Danny C.,Wolf, Joris J.,Mecinovi?, Jasmin
, p. 6536 - 6545 (2019/05/24)
We report an efficient catalytic Staudinger reduction at room temperature that enables the preparation of a structurally diverse set of amines from azides in excellent yields. The reaction is based on the use of catalytic amounts of triphenylphosphine as a phosphine source and diphenyldisiloxane as a reducing agent. Our catalytic Staudinger reduction exhibits a high chemoselectivity, as exemplified by reduction of azides over other common functionalities, including nitriles, alkenes, alkynes, esters, and ketones.
Hydrosilane Reduction of Nitriles to Primary Amines by Cobalt-Isocyanide Catalysts
Sanagawa, Atsushi,Nagashima, Hideo
supporting information, p. 287 - 291 (2019/01/10)
Reduction of nitriles to silylated primary amines was achieved by combination of 1,1,3,3-tetramethyldisiloxane (TMDS) as the hydrosilane and a catalytic amount of Co(OPIV)2 (PIV = COtBu) associated with isocyanide ligands. The resulting silylated amines were subjected to acid hydrolysis or treatment with acid chlorides to give the corresponding primary amines or imides in good yields. One-pot synthesis of primary amides to primary amines with hydrosilanes was also achieved by iron-cobalt dual catalyst systems.
