The arylation of C–H bonds to generate heteroaryl–aryl (Het–Ar) and arylated quinone (Quin–Ar) compounds has received great attention to achieve sustainable goals in synthetic chemistry. Despite significant advances, arylation of a broad range of Het–Ar and Quin–Ar derivatives remains a challenging task. Herein, a variety of heterocycles are arylated by using arylboronic acids in the presence of catalytic
Generation of Arylated Quinones by Iron-Catalyzed Oxidative Arylation of Phenols: Formal Synthesis of Phellodonin, Sarcodonin ε, Leucomelone and Betulinan A
Biologically and pharmaceutically relevant arylatedquinones (Quin‐Ar) have been synthesized via direct CH arylation of a variety of phenols using arylboronic acids. An inexpensive, environmentally friendly iron catalyst, ferric sulphate, Fe2(SO4)3, was employed in this operationally simple and efficient method.
C–H arylation reactions through aniline activation catalysed by a PANI-g-C<sub>3</sub>N<sub>4</sub>-TiO<sub>2</sub> composite under visible light in aqueous medium
作者:Liang Wang、Jun Shen、Sen Yang、Wenjie Liu、Qun Chen、Mingyang He
DOI:10.1039/c8gc00012c
日期:——
composite was prepared and found to be efficient for radical C–H arylationreactions. The arylation process involved coupling of in situ generated aryl diazonium salts from aniline with heteroarenes, enol acetates or benzoquinones under visible light in aqueous medium or pure water. A broad range of substrates survived the reaction conditions to provide the desired products in moderate to good yields
制备了聚苯胺(聚苯胺)-gC 3 N 4 -TiO 2复合材料,发现它对自由基CHH芳基化反应有效。芳基化过程涉及在水性介质或纯水中在可见光下将苯胺的原位生成的芳基重氮盐与杂芳烃,烯醇乙酸酯或苯醌结合。各种各样的底物在反应条件下均能幸存,以中等至良好的产率提供所需的产物。还实现了放大(10 mmol)合成。该半导体光催化剂显示出良好的光催化性能和稳定性。循环研究表明,这种复合材料很容易被回收,连续十次运行后,催化活性略有下降。
Rh-Catalyzed Reactions of 1,4-Benzoquinones with Electrophiles: C–H Iodination, Bromination, and Phenylselenation
作者:Guilherme A. M. Jardim、John F. Bower、Eufrânio N. da Silva Júnior
DOI:10.1021/acs.orglett.6b01586
日期:2016.9.16
4-benzoquinones exhibit nucleophilic reactivity, such that exposure to appropriate electrophiles generates products of C–H iodination, bromination, and phenylselenation. This provides a mild and general method for direct halofunctionalization, and the first method that can achieve direct C–H phenylselenation of this compound class. The scope and limitations of the new protocols are outlined, and representative
Practical C−H Functionalization of Quinones with Boronic Acids
作者:Yuta Fujiwara、Victoriano Domingo、Ian B. Seiple、Ryan Gianatassio、Matthew Del Bel、Phil S. Baran
DOI:10.1021/ja111152z
日期:2011.3.16
quinones with several boronic acids has been developed. This scalable reaction proceeds readily at room temperature in an open flask using inexpensive reagents: catalytic silver(I) nitrate in the presence of a persulfate co-oxidant. The scope with respect to quinones is broad, with a variety of alkyl- and arylboronicacids undergoing efficient cross-coupling. The mechanism is presumed to proceed through