A Pincer Ruthenium Complex for Regioselective C–H Silylation of Heteroarenes
摘要:
A pincer Ru(II) catalyst for the highly efficient undirected silylation of O- and S-heteroarenes with (TMSO)(2)MeSiH and Et3SiH is described, producing heteroarylsilanes with exclusive C2-regioselectivity, good functional group tolerance, and high turnover numbers (up to 1960). The synthetic utility of the silylated products is demonstrated by Pd-catalyzed Hiyama-Denmark cross-coupling under mild conditions. One-pot, two-step silylation and coupling procedures have been also developed.
One-Step Synthesis of Substituted Benzofurans from <i>ortho</i>
- Alkenylphenols <i>via</i>
Palladium-Catalyzed CH Functionalization
作者:Dejun Yang、Yifei Zhu、Na Yang、Qiangqiang Jiang、Renhua Liu
DOI:10.1002/adsc.201600082
日期:2016.6.2
A dehydrogenative oxygenation of C(sp2)H bonds with intramolecular phenolic hydroxy groups has been developed, which provides a straightforward and concise access to structurally diversely benzofuransfrom ortho‐alkenylphenols. The reaction is catalyzed by palladium on carbon (Pd/C) without any oxidants and sacrificing hydrogen acceptors.
Heterocyclensynthesen mit MF/Al2O3-Basensystemen: 2-Arylbenzofurane and 2,3-Diarylisochinolin-1(2H)-one
作者:D. Hellwinkel、K. Göke
DOI:10.1055/s-1995-4057
日期:1995.9
Synthesis of Heterocycles with MF/Al 2 O 3 Base-Systems: 2-Arylbenzofuranes and 2,3-Diarylisoquinolin-1(2H)-ones2-Benzyloxybenzaldehydes, -acetophenones and -benzophenones substituted in the benzyl part with electron-withdrawing groups, cyclize easily to 2-arylbenzofuranes by using a standardized KF- or CsF-Al2O3 base system. An efficient one-pot synthesis for 2,3-diarylisoquinolin-1(2H)-ones is possible by reacting a variety of arene carbaldehyde anils with phthalides under the same reaction conditions.
The first example of sole direct C–H bond arylation of benzo[b]furans with aryl chlorides was achieved catalyzed by a well-defined NHC-Pd(II)-Im complex. Under the suitable conditions, all reactions involving kinds of benzo[b]furans and (hetero)aryl chlorides proceeded well to give the desired C2-arylated benzo[b]furans in sole regioselectivity in acceptable to high yields, providing an efficient and
明确定义的NHC-Pd(II)-Im络合物催化了苯并[ b ]呋喃与芳基氯的唯一直接C-H键芳基化反应。在合适的条件下,所有涉及各种苯并[ b ]呋喃和(杂)芳基氯化物的反应均能顺利进行,从而以唯一的区域选择性提供所需的C2-芳基化苯并[ b ]呋喃,并以高收率接受,从而提供了有效而经济的途径用于苯并[ b ]呋喃的直接C2-H键芳基化。
Visible light mediated desilylative C(sp<sup>2</sup>)–C(sp<sup>2</sup>) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(<scp>i</scp>)/Au(<scp>iii</scp>) catalysis
作者:Indradweep Chakrabarty、Manjur O. Akram、Suprakash Biswas、Nitin T. Patil
DOI:10.1039/c8cc03925a
日期:——
Desilylative C(sp2)–C(sp2) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(I)/photoredox catalysis have been reported. The addition of Cu-salts as catalysts was found to be crucial for the success of this transformation.
Hypervalent Iodine(III)-Catalyzed Synthesis of 2-Arylbenzofurans
作者:Fateh Singh、Saeesh Mangaonkar
DOI:10.1055/s-0037-1610650
日期:2018.12
route for the synthesis of 2-arylbenzofurans is described by iodine(III)-catalyzed oxidative cyclization of 2-hydroxystilbenes using 10 mol% (diacetoxyiodo)benzene [PhI(OAc)2] as catalyst in the presence of m-chloroperbenzoic acid. The 2-arylbenzofurans were isolated in good to excellent yields. An alternative route for the synthesis of 2-arylbenzofurans is described by iodine(III)-catalyzed oxidative