Palladium- and Nickel-Catalyzed Cross-Couplings of Unsaturated Halides Bearing Relatively Acidic Protons with Organozinc Reagents
作者:Georg Manolikakes、Carmen Muñoz Hernandez、Matthias A. Schade、Albrecht Metzger、Paul Knochel
DOI:10.1021/jo8015852
日期:2008.11.7
aryl, heteroaryl, alkyl, and benzylic zinc reagents were coupled with unsaturated aryl halides bearing an acidic NH or OH proton, using Pd(OAc)2 (1 mol %) and S-Phos (2 mol %) as catalyst without the need of protecting groups. A similar nickel-catalyzed reaction is described. The relative kinetic basicity of organozinc compounds as well as their stability toward acidic protons is also described.
Borane-Catalyzed C3-Alkylation of Pyridines with Imines, Aldehydes, or Ketones as Electrophiles
作者:Zhong Liu、Jia-Hao He、Ming Zhang、Zhu-Jun Shi、Han Tang、Xin-Yue Zhou、Jun-Jie Tian、Xiao-Chen Wang
DOI:10.1021/jacs.2c00962
日期:2022.3.23
The existing methods, including electrophilic aromatic substitution and C–H activation, often require harsh reaction conditions and excess pyridine and generate multiple regioisomers. Herein, we report a method for borane-catalyzed tandem reactions that result in exclusively C3-selective alkylation of pyridines. These tandem reactions consist of pyridine hydroboration, nucleophilicaddition of the resulting
C3-Selective Trifluoromethylthiolation and Difluoromethylthiolation of Pyridines and Pyridine Drugs via Dihydropyridine Intermediates
作者:Xin-Yue Zhou、Ming Zhang、Zhong Liu、Jia-Hao He、Xiao-Chen Wang
DOI:10.1021/jacs.2c06776
日期:2022.8.17
difluoromethylthiolation of pyridines. The method relies on borane-catalyzed pyridine hydroboration for generation of nucleophilic dihydropyridines; these intermediates react with trifluoromethylthio and difluoromethylthio electrophiles to form functionalized dihydropyridines, which then undergo oxidative aromatization. The method can be used for late-stage functionalization of pyridine drugs for the generation
作者:Jiang, Ziwei、Qin, Yunan、Liao, Guohong、Liu, Li、Luo, Yanling、Li, Quan、Guo, Kun
DOI:10.1002/smll.202402785
日期:——
demonstrates the light-activated rotary motion but emits photons with good quantum yield. A semi-quantitative TD-DFT calculation is also conducted to aid the understanding of the competitive photoluminescence and photoisomerization processes of the motor. Cytotoxicity test shows this motor possesses good biocompatibility, laying a solid foundation for applying it in the bio-environment. The results demonstrated
A rapid approach for the copper, amine, and ligand-free Sonogashira coupling of 4-methyl-7-nonafluorobutylsulfonyloxy coumarins under microwave irradiation
作者:M. Nibin Joy、Yadav D. Bodke、K.K. Abdul Khader、Ayyiliyath M. Sajith
DOI:10.1016/j.tetlet.2014.02.094
日期:2014.4
A rapid, efficient, and reliable access for the synthesis of an assortment of 4-methyl-7-allcyl/aryl/heteroaryl alkynyl coumarins has been developed by the copper, amine, and ligand-free Sonogashira cross-coupling reaction of 4-methyl-7-nonafluorobutylsulfonyloxy coumarin with various terminal alkynes under microwave irradiation. In the presence of a suitable catalyst, base, and solvent, the coupling reaction proceeded smoothly to give the diaryl alkynes in satisfactory to exceptional yields. Nonaflates coupled more efficiently than the corresponding triflates which yielded the detriflated product as well as the hydrolyzed product as competing side products along with the required product. The utilization of TBAF center dot 3H(2)O as a mild base as well as a solvating agent was the key for success of the reaction. (C) 2014 Elsevier Ltd. All rights reserved.