CuFe 2 O 4超顺磁性纳米粒子被用作有效的可循环异构催化剂,用于通过苯并恶唑或苯并噻唑与碘代芳烃的无配体选择性开环反应合成三苯胺。与一系列均相催化剂和非均相催化剂相比,纳米CuFe 2 O 4表现出明显更高的催化效率。可以分离出纳米CuFe 2 O 4通过使用磁体,回收的催化剂可重复使用多次,同时可保持其活性。据我们所知,这是苯并恶唑转化过程中非均相催化的第一个例子,而苯并噻唑向三苯胺的转化尚未见报道。
Cu‐ or Fe‐based catalyst systems have been reported to selectively catalyze the N,N‐diarylation or N‐monoarylation of benzoxazoles ring‐opening with aryliodides in the absence of additional added ligand in polyethyleneglycol under an inert atmosphere. Two types of coupling products (triphenylamines and diphenylamines) have been examined and the reaction routes can be simply controlled by changing
Utilizing the dramaticacceleratingeffect of 2-aminophenols, we developed a copper-catalyzed system for the selective synthesis of di- and triphenylamines. In addition, N- and O-arylation could be achieved in coupling reactions between 2-aminophenol and nitroaryl halides.
Copper-Catalyzed Selective Arylations of Benzoxazoles with Aryl Iodides
作者:Donghae Kim、Kwangho Yoo、Se Eun Kim、Hee Jin Cho、Junseong Lee、Youngjo Kim、Min Kim
DOI:10.1021/acs.joc.5b00019
日期:2015.4.3
A copper-catalyzed direct ring-opening double N-arylation of benzoxazoles with aryl iodides has been developed. The present system exhibits high selectivity despite competition from C-arylation. The selectivity between ring-opening N-arylation and C-arylation was controlled by the choice of reaction vessel. The nitrile bound bis(triphenylphosphine)copper cyanide was identified as the active catalytic species for both reactions, and when combined with a nitrile-containing solvent, enhanced the reaction efficiency.
Synthesis of<i>N</i>-Arylcarbazoles by Palladium-Catalyzed Direct C-H Arylation of 2-(Diarylamino)phenyl Triflates
作者:Koji Uwa、Ya-Yi Tseng、Ken Kamikawa
DOI:10.1002/ejoc.201601467
日期:2017.1.26
The palladium-catalyzeddirectarylation of a series of 2-(diarylamino)phenyl triflates was examined. The triflates were first synthesized in moderate to good yields through the CuI-catalyzed aryl amination of aminophenol and aryl iodides, followed by triflation of the resulting triarylphenols. The thus-obtained 2-(diarylamino)phenyl triflates were subjected to direct C–H arylation under Pd catalysis
Synthesis of triphenylamines via ligand-free selective ring-opening of benzoxazoles or benzothiazoles under superparamagnetic nanoparticle catalysis
作者:Oanh T. K. Nguyen、Long T. Nguyen、Nhu K. Truong、Viet D. Nguyen、Anh T. Nguyen、Nhan T. H. Le、Dung T. Le、Nam T. S. Phan
DOI:10.1039/c7ra06168d
日期:——
CuFe2O4 superparamagnetic nanoparticles were utilized as an effective recyclable heterogeneous catalyst for the synthesis of triphenylamines via the ligand-free selective ring-opening reaction of benzoxazoles or benzothiazoles with iodoarenes. The nano CuFe2O4 demonstrated noticeably higher catalytic efficiency than a series of homogeneous catalysts and heterogeneous catalysts. It was possible to separate
CuFe 2 O 4超顺磁性纳米粒子被用作有效的可循环异构催化剂,用于通过苯并恶唑或苯并噻唑与碘代芳烃的无配体选择性开环反应合成三苯胺。与一系列均相催化剂和非均相催化剂相比,纳米CuFe 2 O 4表现出明显更高的催化效率。可以分离出纳米CuFe 2 O 4通过使用磁体,回收的催化剂可重复使用多次,同时可保持其活性。据我们所知,这是苯并恶唑转化过程中非均相催化的第一个例子,而苯并噻唑向三苯胺的转化尚未见报道。