Palladium-Catalyzed Intramolecular C-H Amination in Water
作者:Lizheng Yang、Hao Li、Haifei Zhang、Hongjian Lu
DOI:10.1002/ejoc.201601043
日期:2016.12
found to be effective for intramolecular C–H amination in water. With 2-azidobiphenyls as substrates, the reaction efficiently provided various carbazoles with N2 as the sole byproduct. The reaction showed high functional-group tolerance and could be used in the synthesis of several natural carbazole alkaloids. The catalytic process was promoted by water, and the reaction was inefficient in the organic
发现钯 (II) 催化对水中的分子内 C-H 胺化有效。以 2-叠氮联苯为底物,该反应有效地提供了各种咔唑,N2 作为唯一的副产物。该反应显示出高官能团耐受性,可用于合成多种天然咔唑生物碱。催化过程受水促进,在所研究的有机溶剂中反应效率低下。
Visible-light-promoted intramolecular C–H amination in aqueous solution: synthesis of carbazoles
作者:Lizheng Yang、Yipin Zhang、Xiaodong Zou、Hongjian Lu、Guigen Li
DOI:10.1039/c7gc03392c
日期:——
An effective and operationally simpleprotocol is reported for the synthesis of versatile carbazoles. With water as a co-solvent, visible-light rather than various metals is used to facilitate the conversion of readily available 2-azidobiphenyls under mild conditions. Various functionalized bioactive natural alkaloids, such as glycoborine, clausine C, clausine L, clausine H and clauszoline K, were
An efficient method for the construction of dibenzo[b,d]azepines containing two distinct stereogenic elements in a highly diastereoselective fashion is described. The key of the [5 + 2] reaction is to form a π-allylpalladium species through sequential C–H activation and regiospecific migratory insertion of the diene. This observation contrasts with the behavior of 1,2-alkenes that generally underwent
The first example of the palladium-catalyzed primary amine-directed C(sp2)–H alkynylation of biaryl-2-amines has been developed by using (bromoethynyl)triisopropylsilane as an alkynylating reagent. This protocol exhibits a broad substrate scope, excellent regioselectivity and gram-scale synthesis. Significantly, the versatility of this straightforward method was further demonstrated by controlled mono-
Highly Stereoselective Synthesis of Imine‐Containing Dibenzo[
<i>b</i>
,
<i>d</i>
]azepines by a Palladium(II)‐Catalyzed [5+2] Oxidative Annulation of
<i>o</i>
‐Arylanilines with Alkynes
A novel palladium(II)‐catalyzed [5+2] oxidativeannulation of readily available o‐arylanilines with alkynes has been developed for building a seven‐membered N‐heterocyclic architecture containing a biaryl linkage. This method is applicable to a wide range of unprotected o‐arylanilines and internal alkynes, and results in the chemoselective preparation of imine‐containingdibenzo[b,d]azepines in high