- Rhodium-catalyzed intermolecular hydroarylation of internal alkynes with N-1-phenylbenzotriazoles
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A rhodium-catalyzed intermolecular hydroarylation of internal alkynes with N-1-phenylbenzotriazoles via C-H bond activation is described. This transformation offers an alternative method for the hydroarylation of internal alkynes with high stereoselectivity. The reaction mechanism was discussed according to the deuterium-labeling experiments.
- Zhou, Wang,Yang, Youqing,Wang, Zhiwei,Deng, Guo-Jun
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- Mild and general access to diverse 1H-benzotriazoles via diboron-mediated N-OH deoxygenation and palladium-catalyzed C-C and C -N bond formation
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Benzotriazoles are a highly important class of compounds with broad-ranging applications in such diverse areas as medicinal chemistry, as auxiliaries in organic synthesis, in metallurgical applications, in aircraft deicing and brake fluids, and as antifog agents in photography. Although there are numerous approaches to N-substituted benzotriazoles, the essentially one general method to N-unsubstituted benzotriazoles is via diazotization of ortho -phenylenediamines, which can be limited by the availability of suitable precursors. Other methods to N-unsubstitued benzotriazoles are quite specialized. Although reduction of 1-hydroxy-1 H-benzotriazoles is known, the reactions are not particularly convenient or broadly applicable. This presents a limitation for easy access to and availability of diverse benzotri-ACHTUNGTRENUNGazoles. Herein, we demonstrate a new, broadly applicable method to diverse 1H-benzotriazoles via a mild diboron reagent-mediated deoxygenation of 1-hydroxy-1H-benzotriazoles. We have also evaluated sequential deoxygenation and Pd-mediated C-C and C-N bond formation as a one-pot process for further diversification of the benzotriazole moiety. However, the results indicated that purification of the deoxygenation product prior to the Pd-mediated reaction is critical to the success of such reactions. The overall chemistry allows for facile access to a variety of new benzotriazoles. Along with the several examples presented, a discussion of the advantages of the approaches is described, as is also a possible mechanism for the deoxygenation process.
- Gurram, Venkateshwarlu,Akula, Hari K.,Garlapati, Ramesh,Pottabathini, Narender,Lakshman, Mahesh K.
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- Relative role of halogen bonds and hydrophobic interactions in inhibition of human protein kinase CK2α by tetrabromobenzotriazole and some C(5)-substituted analogues
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To examine the relative role of halogen bonding and hydrophobic interactions in the inhibition of human CK2α by 4,5,6,7- tetrabromobenzotriazole (TBBt), we have synthesized a series of 5-substituted benzotriazoles (Bt) and the corresponding 5-substituted 4,6,7- tribromobenzotriazoles (Br3Bt) and examined their inhibition of human CK2α relative to that of TBBt. The various C(5) substituents differ in size (H and CH3), electronegativity (NH2 and NO 2), and hydrophobicity (COOH and Cl). Some substituents were halogen bond donors (Cl, Br), while others were fluorine bond donors (F and CF 3). Most of the 5-substituted analogues of Br3Bt (with the exception of COOH and NH2) exhibited inhibitory activity comparable to that of TBBt, whereas the 5-substituted analogues of the parent Bt were only weakly active (Br, Cl, NO2, CF3) or inactive. The observed effect of the volume of a ligand molecule pointed to its predominant role in inhibitory activity, indicating that presumed halogen bonding, identified in crystal structures and by molecular modeling, is dominated by hydrophobic interactions. Extended QSAR analysis additionally pointed to the monoanion and a preference for the N(1)-H protomer of the neutral ligand as parameters crucial for prediction of inhibitory activity. This suggests that the monoanions of TBBt and its congeners are the active forms that efficiently bind to CK2α, and the binding affinity is coupled with protomeric equilibrium of the neutral ligand.
- W?sik, Romualda,?ebska, Maja,Felczak, Krzysztof,Poznański, Jaros?aw,Shugar, David
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- Diarylborinic Acid-Catalyzed Regioselective Ring Openings of Epoxy Alcohols with Pyrazoles, Imidazoles, Triazoles, and Other Nitrogen Heterocycles
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A method for regioselective ring openings of 3,4- and 2,3-epoxy alcohols with ambident nitrogen heterocycles is described. Using a diarylborinic acid catalyst, a single regioisomer is favored in couplings of nucleophile and electrophile partners that display low regioselectivity under conventional conditions. The method provides access to aromatic heterocycles bearing stereochemically defined, functionalized alkyl substituents, a product class similar in structure to medicinally relevant compounds such as the acyclic nucleoside analogues.
- Desai, Shrey P.,Taylor, Mark S.
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supporting information
p. 7049 - 7054
(2021/09/13)
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- Synthesis of Structurally Diverse Benzotriazoles via Rapid Diazotization and Intramolecular Cyclization of 1,2-Aryldiamines
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An operationally simple method has been developed for the preparation of N-unsubstituted benzotriazoles by diazotization and intramolecular cyclization of a wide range of 1,2-aryldiamines under mild conditions, using a polymer-supported nitrite reagent and p-tosic acid. The functional group tolerance of this approach was further demonstrated with effective activation and cyclization of N-alkyl, -aryl, and -acyl ortho-aminoanilines leading to the synthesis of N1-substituted benzotriazoles. The synthetic utility of this one-pot heterocyclization process was exemplified with the preparation of a number of biologically and medicinally important benzotriazole scaffolds, including an α-amino acid analogue.
- Faggyas, Réka J.,Sloan, Nikki L.,Buijs, Ned,Sutherland, Andrew
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p. 5344 - 5353
(2019/05/21)
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- Tert -Butyl nitrite mediated nitrogen transfer reactions: Synthesis of benzotriazoles and azides at room temperature
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A conversion of o-phenylenediamines into benzotriazoles was achieved at room temperature using tert-butyl nitrite. The optimized conditions are also well suited for the transformation of sulfonyl and acyl hydrazines into corresponding azides. This protocol does not require any catalyst or acidic medium. The desired products were obtained in excellent yields in a short span of time.
- Azeez, Sadaf,Chaudhary, Priyanka,Sureshbabu, Popuri,Sabiah, Shahulhameed,Kandasamy, Jeyakumar
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supporting information
p. 6902 - 6907
(2018/10/02)
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- Molybdenum-Catalyzed Deoxygenation of Heteroaromatic N-Oxides and Hydroxides using Pinacol as Reducing Agent
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A molybdenum-catalyzed deoxygenation of pyridine N-oxides and N-hydroxybenzotriazoles, as well as other azole N-oxides, has been developed using pinacol as an environmentally friendly oxo-acceptor. The only by-products are acetone and water making the process a convenient alternative to established protocols in terms of waste generation. The reaction is highly chemoselective and a variety of functional groups are tolerated. The processes are usually very clean allowing the isolation of the pure deoxygenated products after a simple extraction in most cases. (Figure presented.).
- Rubio-Presa, Rubén,Fernández-Rodríguez, Manuel A.,Pedrosa, María R.,Arnáiz, Francisco J.,Sanz, Roberto
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supporting information
p. 1752 - 1757
(2017/05/22)
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- ENANTIOMERICALLY ENRICHED ARYLOAZOL-2-YL CYANOETHYLAMINO COMPOUNDS, METHOD OF MAKING AND METHOD OF USING THEREOF
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The present invention relates to novel aryloazol-2-yl-cyanoethylamino derivatives substantially enriched in an enantiomer of formula (I): and compounds of formula (IH) wherein R3, R4, R5, R6, R7, R13a, R13b, R14a, R14b, P, Q, V, W, X, Y, Z and a are as defined in the description, compositions thereof, processes for their preparation and their uses as pesticides.
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Page/Page column 43
(2010/06/13)
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- ARYLOAZOL-2-YL CYANOETHYLAMINO COMPOUNDS, METHOD OF MAKING AND METHOD OF USING THEREOF
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The present invention relates to novel aryloazol-2-yl-cyanoethylamino derivatives of formula (I):wherein R3, R4, R5, R6, R7, P, Q, V, W, X, Y, Z and a are as defined in the description, compositions thereof, processes for their preparation and their uses as pesticides.
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Page/Page column 52
(2009/01/20)
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- Controlled synthesis of electron deficient nitro-1H-benzotriazoles
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Nitro-1H-benzotriazole derivatives containing electron withdrawing substitutents in the ortho and meta positions to the nitro group have been synthesized by the simple and direct nitration of the parent 1H-benzotriazoles. The route of nitration and assignment of isomerism in these compounds is proposed based upon high level density functional theory (DFT) calculations.
- McHugh, Callum J.,Tackley, Daniel R.,Graham, Duncan
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p. 1461 - 1470
(2007/10/03)
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