S RN 1反应已被用作合成杂环的有力工具,并且仅报道了少数有关通过自由基途径光诱导分子内环化以生成新的C-O键的研究。这项工作介绍了两种通过电子转移(eT)反应合成取代的二苯并呋喃的策略。第一个是三步过程,其中包括溴化o-芳基苯酚,Suzuki-Miyaura交叉偶联和光诱导的环化反应,以获得上述产物。第二种是无金属工艺,不需要任何光催化剂。测试了不同的溶剂,收率范围从低到中等。在两种方法之间建立了比较,表明第二种方法最适合合成二苯并呋喃。
Synthesis of Ladder-Type π-Conjugated Heteroacenes via Palladium-Catalyzed Double N-Arylation and Intramolecular O-Arylation
作者:Keiko Kawaguchi、Koji Nakano、Kyoko Nozaki
DOI:10.1021/jo070427p
日期:2007.7.1
d‘]benzo[1,2-b:4,5-b‘]difurans, were effectively synthesized from the common intermediates, 2,5-bis(o-chloroaryl)hydroquinones. The key reactions are palladium-catalyzed double N-arylation of aniline and intramolecular O-arylation, which enable regioselective ring closure. In addition to the parent indolo[3,2-b]carbazole and dibenzo[d,d‘]benzo[1,2-b:4,5-b‘]difuran, their derivatives with an alkyl or cyano
可以有效地合成含有吡咯或呋喃环,吲哚并[3,2- b ]咔唑和二苯并[ d,d ']苯并[1,2- b:4,5- b ']二呋喃的阶梯型杂并苯中间体2,5-双(邻氯芳基)氢醌。关键反应是钯催化的苯胺双N-芳基化和分子内的O-芳基化,从而实现区域选择性的闭环。除了母体吲哚[3,2- b ]咔唑和二苯并[ d,d ']苯并[1,2- b:4,5- b首先合成了′]二呋喃,其具有烷基或氰基的衍生物。光物理和电化学研究表明,与相应的烃并苯,并五苯相比,所获得的杂苯具有较低的HOMO能级和较大的带隙。对二苯并[ d,d ']苯并[1,2- b:4,5- b ']二呋喃的X射线分析表明,其以人字形包装。
Ammonium Salt-Catalyzed Highly Practical <i>Ortho</i>-Selective Monohalogenation and Phenylselenation of Phenols: Scope and Applications
作者:Xiaodong Xiong、Ying-Yeung Yeung
DOI:10.1021/acscatal.8b00327
日期:2018.5.4
An ortho-selective ammonium chloride salt-catalyzed direct C–H monohalogenation of phenols and 1,1′-bi-2-naphthol (BINOL) with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) as the chlorinating agent has been developed. The catalyst loading was low (down to 0.01 mol %) and the reaction conditions were very mild. A wide range of substrates including BINOLs were compatible with this catalytic protocol. Chlorinated
Synthesis of 2,2′-biphenols through direct C(sp<sup>2</sup>)–H hydroxylation of [1,1′-biphenyl]-2-ols
作者:Shitao Duan、Yuanshuang Xu、Xinying Zhang、Xuesen Fan
DOI:10.1039/c6cc04756d
日期:——
A novel synthesis of diversely substituted 2,2′-biphenols through Pd(ii)-catalyzed,tBuOOH-oxidized, and hydroxyl-directed C(sp2)–H hydroxylation of [1,1′-biphenyl]-2-ols has been developed.
This invention concerns the synthesis of polycyclic structural components of pharmacological compounds, including the synthesis of fused benzofuro-heterocycles, through selective palladium-catalyzed cross-coupling and intramolecular cyclization.
Synthesis of hydroxylated oligoarene-type phosphines by a repetitive two-step method
作者:Shunpei Ishikawa、Kei Manabe
DOI:10.1016/j.tet.2009.10.101
日期:2010.1
oligoarene-type phosphines with various substitution patterns were synthesized. Such phosphines have potential as ligands for transition metal-catalyzed reactions. A successful route, which includes a repetitive Suzuki–Miyaura coupling–triflation sequence, reduction, and salt formation, was established starting from 2-bromophenyldicyclohexylphosphine oxide. Other key aspects of the method are the use of