25069-88-9Relevant articles and documents
COMPOUND WHICH INHIBITS TELOMERE-BINDING PROTEIN, AND TELOMERE-BINDING PROTEIN INHIBITOR CONTAINING SAME
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Paragraph 0086, (2021/01/29)
The compound according to the present invention is a compound represented by the following chemical formula: wherein, in the above-described chemical formula, R1 is oxygen or sulfur, and R2 to R6 are each independently sel
Synthesis of triphenylamines: Via ligand-free selective ring-opening of benzoxazoles or benzothiazoles under superparamagnetic nanoparticle catalysis
Nguyen, Oanh T.K.,Nguyen, Long T.,Truong, Nhu K.,Nguyen, Viet D.,Nguyen, Anh T.,Le, Nhan T.H.,Le, Dung T.,Phan, Nam T.S.
, p. 40929 - 40939 (2017/09/01)
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 the nano CuFe2O4 by using a magnet, and the recovered catalyst was reused many times while its activity could be maintained. To the best of our knowledge, this is the first example of heterogeneous catalysis for the transformation of benzoxazoles, and the transformation of benzothiazoles to triphenylamines has not been previously reported in the literature.
Ligand-Free, Cu- and Fe-Catalyzed Selective Ring-Opening Arylations of Benzoxazoles with Aryl Iodides
He, Yue,Mao, Jincheng,Rong, Guangwei,Yan, Hong,Zhang, Guoqi
supporting information, p. 1672 - 1676 (2016/06/14)
Cu- or Fe-based catalyst systems have been reported to selectively catalyze the N,N-diarylation or N-monoarylation of benzoxazoles ring-opening with aryl iodides in the absence of additional added ligand in polyethylene glycol 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 the metal salts (Cu or Fe) as catalyst. A range of substrates have been investigated for the diverse reactions, and the corresponding arylation products were achieved in good to high yields. This selective, low-cost, and environmentally friendly protocol displays great potential for replacing existing methodologies as well as extending the synthetic applications of benzoxazoles.
