Base-Mediated N- and O-Arylations of NH-Containing Heterocycles, Heterocyclic Amines and Phenols

Abstract

Nucleophilic substitution reactions of N-heterocycles such as imidazole, benzimidazole, indole and pyrazole as well as NH 2 or OH containing heterocycles, with electron-deficient aryl halides in the presence of t-BuOK or K 2 CO 3 as base and DMSO as solvent are reported. A series of N-aryl azoles, unsymmetric diaryl ethers and diaryl amines were obtained in good yields.

Bismuth(III)--SiO$_{2}$ catalyzed synthesis of polysubstituted imidazoles with the participation of azaaryl derivatives of aniline in four-component reactions

“…We recently reported the tert-BuOK/DMSO-promoted S N Ar reactions of azoles such as imidazole, benzimidazole, pyrazole, and 3-methypyrazole with 4-bromonitrobenzene to obtain N -(4-nitrophenyl) azoles 1a-d. 32 Reduction of the nitro group to amine with zinc powder in EtOH/AcOH afforded the required aniline derivatives Firstly, we used 4-(3-methyl-1H -pyrazol-1-yl)aniline 2d (1 mmol) in four-component condensation with benzil (1 mmol), benzaldehyde (1 mmol), and ammonium acetate (1 mmol) to find the optimal reaction conditions. As shown in Table 1, in the absence of a catalyst, no product was obtained in the presence of solvent or without solvent, even after 48 h (Entries 1-6).…”

The Structure ofN‐phenyl‐pyrazoles and Indazoles: Mononitro, Dinitro, and Trinitro Derivatives

“…For the second one, compound 36 : microwave irradiation ; Cu(I) catalysts: copper‐anchored porous zinc‐based metal–organic framework heterogeneous conditions , sulfonic acid‐based cation‐exchanger resin “INDION 770” , 8‐hydroxyquinoline‐ N ‐oxide ligand for CuBr , 10 mol% of CuI as catalyst and 1.2 equivalent NaH as base , CuI in ionic liquid [Bmim]BF 4 as a reaction medium , phosphine‐diolefin cubane copper pre‐catalyst , Salen‐Cu(II) complex , activated‐copper powder in water with LiOH as base , copper(I) 3‐methylsalicylate , 3‐(diphenylphosphino)propanoic acid an efficient ligand for Cu‐catalysts , metal–organic framework [Cu(INA) 2 ] as heterogeneous catalyst , surfactant/copper‐based ionic liquid/water , and for a general discussion about the frontier between nucleophilic aromatic substitution and catalysis, see ; the use of t‐BuOK or K 2 CO 3 in dimethyl sulfoxide has been updated .…”