2296-13-1Relevant academic research and scientific papers
Osmium-Promoted Transformation of Alkyl Nitriles to Secondary Aliphatic Amines: Scope and Mechanism
Babón, Juan C.,Esteruelas, Miguel A.,López, Ana M.,O?ate, Enrique
supporting information, p. 2177 - 2188 (2020/06/08)
The transformation of alkyl nitriles to symmetrical and asymmetrical secondary aliphatic amines promoted by the hexahydride complex OsH6(PiPr3)2 (1) is described, and the mechanisms of the reactions involved are established. Complex 1 catalyzes the aforementioned transformations of aryl-, pyridyl-, and alkoxy-functionalized alkyl nitriles with linear or branched chains. The formation of the secondary amines involves primary imines, primary amines, and secondary imines as organic intermediates. The reactions take place under mild conditions (toluene, 100 °C, and 4 bar of H2). Stoichiometric reactions of 1 with pivalonitrile and 2-methoxyacetonitrile have allowed us to isolate the trihydride azavinylidene derivatives OsH3{═N═CHR}(PiPr3)2 (R = tBu (3), CH2OMe (4)). Their formation involves the insertion of the N-C triple bond of the substrates into an Os-H bond of the unsaturated tetrahydride OsH4(PiPr3)2 (A), which is generated by reductive elimination of H2 from the hexahydride precursor. The reaction of these trihydride azavinylidene species with H2 is the key step for the reduction of the N-C triple bond of the nitriles. In the absence of H2, the attack of A to the azavinylidene ligand produces the rupture of its C(sp2)-C(sp3) bond. As a consequence of this attack and the presence of primary imines and amines in the reaction media, the binuclear complexes (PiPr3)2H4Os(μ-CN)OsH3{κ1-N-(NH═CHCH2OMe)}(PiPr3)2 (5) and (PiPr3)2H4Os(μ-CN)OsH3{κ1-N-(NH2CH2CH2OMe)}(PiPr3)2 (6) have been isolated and characterized by X-ray diffraction analysis, for 2-methoxyacetonitrile. DFT calculations reveal noticeable similarities between the hydrogenations of nitriles to primary imines and those of primary imines to primary amines.
Designing Simple Lipidated Lysines: Bifurcation Imparts Selective Antibacterial Activity
Ghosh, Chandradhish,Konai, Mohini Mohan,Sarkar, Paramita,Samaddar, Sandip,Haldar, Jayanta
supporting information, p. 2367 - 2371 (2016/11/13)
In the global effort to thwart antimicrobial resistance, lipopeptides are an important class of antimicrobial agents, especially against Gram-negative infections. In an attempt to circumvent their synthetic complexities, we designed simple membrane-active agents involving only one amino acid and two lipid tails. Herein we show that the use of two short lipid tails instead of a single long one significantly increases selective antibacterial activity. This study yielded several selective antibacterial compounds, and investigations into the properties of this compound class were conducted with the most active compound. Fluorescence spectroscopic studies revealed the capacity of the representative compound to cause depolarization and permeabilization of bacterial cell membranes. This membrane-active nature of the compound imparts superior activity against persister cells, biofilms, and planktonic cells. Topical application of the compound decreased bacterial burden in mice inflicted with burn-infections caused by Acinetobacter baumannii. We anticipate that the design principles described herein will direct the development of several antimicrobial agents of clinical importance.
Selective complexation of di-: N -hexylammonium salts by tailed porphyrin host
Liu, Hui,Tu, Ji-Qiang,Zhang, Cheng-Hua,Xiao, Qiao-Ting,Wang, Tian-Hua,Ju, Xiu-Lian
supporting information, p. 5679 - 5682 (2016/07/19)
Novel types of tailed porphyrins have been synthesized and characterized. The tail was coordinated intramolecularly to zinc porphyrin, leading to the formation of a cavity. In the cavity, tailed porphyrins formed a complex with di-n-hexylammonium salts. T
Nucleophilic substitution reaction at the nitrogen of arylsulfonamides with phosphide anion
Yoshida, Suguru,Igawa, Kazunobu,Tomooka, Katsuhiko
supporting information, p. 19358 - 19361 (2013/02/22)
A novel nucleophilic substitution reaction at the nitrogen of arylsulfonamides by means of phosphide anions has been described. This reaction allows for the efficient transformation of arylsulfonamides into synthetically valuable phosphamides, amines, and a variety of protected amines.
Threading the calix[5]arene annulus
Gattuso, Giuseppe,Notti, Anna,Parisi, Melchiorre F.,Pisagatti, Ilenia,Amato, Maria E.,Pappalardo, Andrea,Pappalardo, Sebastiano
body text, p. 2381 - 2385 (2010/06/17)
Slowly does it! Di-n-alkylammonium ions (such as 2 H+) thread the annulus of calix[5]arene 1 to yield stable [2] pseudorotaxanes. The ease of formation of this hitherto unknown family of interpenetrated supermolecules is predominantly determine
Contribution a l'evaluation de l'importance des facteurs electroniques et steriques gouvernant la reaction des boranes avec les azides
Carboni, Bertrand,Vaultier, Michel,Courgeon, Thierry,Carrie, Robert
, p. 844 - 849 (2007/10/02)
Organoboranes react with azides to give, after hydrolysis, secondary amines.Scope and limitations of this method have been stated.When dibromoboranes were used, a competitive migration of the alkyl group and bromine leading to the simultaneous formation of a tetraazaboroline and the expected secondary amine was observed.A mechanism accounting for these results is proposed.
