Reductive Molybdenum-Catalyzed Direct Amination of Boronic Acids with Nitro Compounds
The synthesis of aromatic amines is of utmost importance in a wide range of chemical contexts. We report a direct amination of boronic acids with nitro compounds to yield (hetero)aryl amines. The novel combination of a dioxomolybdenum(VI) catalyst and triphenylphosphine as inexpensive reductant has revealed to be decisive to achieve this new C?N coupling. Our methodology has proven to be scalable, air and moisture tolerant, highly chemoselective and engages both aliphatic and aromatic nitro compounds. Moreover, this general and step-economical synthesis of aromatic secondary amines showcases orthogonality to other aromatic amine syntheses as it tolerates aryl halides and carbonyl compounds.
Suárez-Pantiga, Samuel,Hernández-Ruiz, Raquel,Virumbrales, Cintia,Pedrosa, María R.,Sanz, Roberto
supporting information
p. 2129 - 2133
(2019/01/25)
Copper immobilized at a covalent organic framework: An efficient and recyclable heterogeneous catalyst for the Chan-Lam coupling reaction of aryl boronic acids and amines
A polyimide covalent organic framework (PI-COF) with high thermal and chemical stabilities has been readily prepared from commercially available and inexpensive reagents and was employed as an effective support for heterogeneous copper. It was demonstrated that the obtained Cu@PI-COF is a highly active heterogeneous catalyst which can effectively promote the Chan-Lam coupling reaction of aryl boronic acids and amines in an open flask without the aid of any base or additive. In addition, the catalyst could be readily recovered from the reaction mixture by simple filtration and reused for at least eight cycles without any observable change in structure and catalytic activity.
Han, Yi,Zhang, Mo,Zhang, Ya-Qing,Zhang, Zhan-Hui
p. 4891 - 4900
(2018/11/21)
Reaction of phenylhydrazines with arenes in the presence of aluminium trichloride
Phenylnitrenium ions are generated from phenylhydrazines by treatment with AlCl3. Reaction of a phenylnitrenium ion with arenes results in both aromatic N-substitution and C-substitution. In contrast, an N-methylphenylnitrenium ion undergoes exclusively aromatic C-substitution. Reaction of a phenylnitrenium ion with arenes present only in slight excess produces anilinated products in moderate to good yields.
Ohwada,Nara,Sakamoto,Kikugawa
p. 3064 - 3068
(2007/10/03)
Synthesis of novel (bis)(diarylamino)thiophenes via palladium-catalysed reaction of (di)bromothiophenes with diarylamines
Synthesis of novel (bis)(diarylamino)thiophenes including 2,5- bis(diarylamino)thiophenes was attained by PBu(t)3-ligated palladium- catalysed coupling of (di)bromothiophenes with diarylamines.