14062-20-5Relevant academic research and scientific papers
Preparation method of ibuprofen impurity N
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Paragraph 0007; 0024, (2021/03/30)
The invention provides a preparation method of an ibuprofen impurity N, and belongs to the technical field of preparation of drug impurity standard substances, and the preparation method comprises thefollowing steps: step 1, carrying out coupling reaction
Iron and manganese catalysts for the selective functionalization of arene C(sp2)-H bonds by carbene insertion
Conde, Ana,Sabenya, Gerard,Rodríguez, Mònica,Postils, Verònica,Luis, Josep M.,Díaz-Requejo, M. Mar,Costas, Miquel,Pérez, Pedro J.
supporting information, p. 6530 - 6534 (2016/06/01)
The first examples of the direct functionalization of non-activated aryl sp2 C-H bonds with ethyl diazoacetate (N2CHCO2Et) catalyzed by Mn- or Fe-based complexes in a completely selective manner are reported, with no formation of the frequently observed cycloheptatriene derivatives through competing Buchner reaction. The best catalysts are FeII or MnII complexes bearing the tetradentate pytacn ligand (pytacn= 1-(2-pyridylmethyl)-4,7-dimethyl-1,4,7-triazacyclononane). When using alkylbenzenes, the alkylic C(sp3)-H bonds of the substituents remained unmodified, thus the reaction being also selective toward functionalization of sp2 C-H bonds. Exclusive catalysis: Iron- and-manganese-based catalysts selectively functionalize the C(sp2)-H bonds of benzene or alkylbenzenes through the formal insertion of the CHCO2Et group from N2CHCO2Et (see scheme). When using alkylbenzenes, the alkylic C(sp3)-H bonds of the substituents remain unmodified.
