183280-13-9Relevant academic research and scientific papers
Copper-Mediated Functionalization of Aryl Trifluoroborates
Schimler, Sydonie D.,Sanford, Melanie S.
, p. 2279 - 2284 (2016)
This paper describes the Cu(OTf)2-mediated coupling of aryl and heteroaryl trifluoroborates with tetrabutylammonium or alkali metal salts to form C-O, C-N, and C-halogen bonds. The reactions proceed under mild conditions (often room temperature over 16 hours) with carboxylate, halide, and azide salts, all nucleophiles that have been underrepresented in the copper cross-coupling literature. Preliminary results show that copper salts bearing weakly coordinating X-type ligands are essential for enabling these transformations to proceed under mild conditions.
Regioselective Ortho‐C–H sulfenylation of free phenols catalyzed by Co(II)-immobilized on silica-coated magnetic nanoparticles
Khaef, Sepideh,Rostami, Abed,Khakyzadeh, Vahid,Zolfigol, Mohammad Ali,Taherpour, Avat Arman,Yarie, Meysam
, (2020/01/22)
Fe3O4?SiO2-UT?CoII is prepared by the silica-coated magnetic nanoparticles, urea-triazole, and CoCl2. This organic-inorganic hybride composite showed a good to excellent catalytic activity toward regioselective ortho-sulfenylation of free phenols and naphthols using pivalic anhydride as a directing group, also K2S2O8 and PPh3 were employed as oxidant and additive respectively. The newly synthesized catalyst was fully characterized by using different techniques such as FT-IR, TGA, DTG, TEM, SEM, EDS, ICP and VSM analyses. The competitive price, accessibility and lower toxicity of cobalt compared to expensive transition metals using for C–H bond activation and functionalization constitute precious advantages for this method. Moreover, this heterogeneous catalyst could be magnetically recovered and reused without significant loss of its catalytic activity after five cycles.
Nickel-Catalyzed Phosphorylation of Phenol Derivatives via C-O/P-H Cross-Coupling
Yang, Jia,Xiao, Jing,Chen, Tieqiao,Han, Li-Biao
, p. 3911 - 3916 (2016/05/24)
An efficient nickel-catalyzed phosphorylation of phenol derivatives with P(O)-H compounds via C-O/P-H cross-coupling is described. Under the reaction conditions, various phenyl pivalates coupled readily with hydrogen phosphoryl compounds to afford the corresponding coupling products aryl phosphonates and aryl phosphine oxides in good to high yields.
A general copper-mediated nucleophilic 18F fluorination of arenes
Tredwell, Matthew,Preshlock, Sean M.,Taylor, Nicholas J.,Gruber, Stefan,Huiban, Mickael,Passchier, Jan,Mercier, Joel,Genicot, Christophe,Gouverneur, Veronique
supporting information, p. 7751 - 7755 (2014/08/05)
Molecules labeled with fluorine-18 are used as radiotracers for positron emission tomography. An important challenge is the labeling of arenes not amenable to aromatic nucleophilic substitution (SNAr) with [ 18F]F-. In the
Nickel-catalyzed amination of aryl Pivalates by the cleavage of aryl C-O bonds
Shimasaki, Toshiaki,Tobisu, Mamoru,Chatani, Naoto
supporting information; experimental part, p. 2929 - 2932 (2010/06/15)
(Figure Presented) Catalytic animation: The title reaction demonstrates the use of aryl carboxylates as suitable electrophilic coupling substrates in catalytic amination reactions. Nheterocyclic carbene ligands and NaOtBupromote the amination of aryl pivalates through the cleavage of normally unreactive aryl carbon-oxygen bonds (see scheme; cod = cyclooctadiene).
1-(2,5-dichlorophenyl)-2,2-bis(methylsulfanyl)vinyl esters as highly efficient chemoselective acylating reagents
Degani,Dughera,Fochi,Serra
, p. 1200 - 1208 (2007/10/03)
1-(2,5-Dichlorophenyl)-2,2-bis(methylsulfanyl)vinyl esters 4f-k were prepared in yields usually greater than 90%, by reacting acyl chlorides with 1-(2,5-dichlorophenyl)-2,2-bis(methylsulfanyl)ethanone enolate. These esters were demonstrated to be excellent chemoselective reagents for the acylation of amines, alcohols, thiols, pyrrole and indole. From all the acylation reactions the dimethyl α-oxo dithioacetal 2d, recyclable for the preparation of esters 4f-k, could be recovered in 90-100% yield.
Structure-activity relationships of novel azomethine prodrugs of the histamine H3-receptor agonist (R)-α-methylhistamine: From alkylaryl to substituted diaryl derivatives
Krause,Rouleau,Stark,Garbarg,Schwartz,Schunack
, p. 720 - 726 (2007/10/03)
This study was performed on the basis of recently developed prodrugs of the histamine H3-receptor agonist (R)-α-methylhistamine (1) to determine structure-activity relationships of azomethine prodrugs of 1, in which the primary amine functionality is bioreversibly linked to aromatic ketones. Therefore, the pro-moiety was systematically altered from alkylaryl over benzylaryl to diaryl substitution. Those compounds that emerged to be stable enough during preparation were tested for their in vitro hydrolysis rates. Apparently, bulky alkyl residues were capable of preventing previously observed intramolecular cyclization, but the obtained azomethines 12 a-c were far too unstable to serve as prodrugs. However, the benzylaryl imines 12d, e were stable compounds, but 12d decomposed too rapidly under in vitro conditions. Distinctly greater stability was provided by diaryl pro-moieties, even if strongly electron-withdrawing functionalities were introduced. Selected compounds were also tested in vivo following p.o. application to mice. Particularly the trifluoromethyl substituted imine 12i proved to be highly effective as stability and rate of conversion were well-balanced, so that brain penetration of 1 was strikingly facilitated. Thus 12i, a highly potent azomethine prodrug, may serve as an important pharmacological tool and, possibly, a therapeutic agent.
