Synthesis of heteroaryl ketones via tandem reaction of 1,1-dibromoethenes
摘要:
A novel method for the synthesis of heteroaryl ketones through one-pot tandem reaction of 1,1-dibromoethenes with 2-amino(thio)phenols promoted by TBAF center dot 3H(2)O and RuCl3(5%)/air was developed. This novel method includes several reactions in one-pot and utilizes economical yet efficient reagents to generate synthetically and biologically interesting heteroaryl ketones under mild conditions with good efficiency. (C) 2011 Elsevier Ltd. All rights reserved.
I2 and TBHP is described. Acylation of the benzothiazoles is achieved through a sequence involving oxidation of the aryl ketone to an aryl glyoxal, ring-opening of the benzothiazole followed by condensation of the amino group with the aryl glyoxal, cyclization and oxidation. The method avoids the use of metals and toxic solvents. In addition, this protocol has the advantage of broad scope and provides
via AlCl3-mediated cyclization reaction and I2-promoted sequential oxidation reaction of 2-aminobenzenethiols with arylacetonitriles was developed. This reaction proceeds smoothly with a wide range of arylacetonitriles containing different functional groups to give the corresponding products in moderate to good yields under mild conditions. Moreover, this reaction was conveniently conducted on a gram
开发了一种有效的一锅法,通过AlCl 3介导的环化反应和 I 2促进的 2-氨基苯硫醇与芳基乙腈的顺序氧化反应获得 2-酰基苯并噻唑。该反应与各种含有不同官能团的芳基乙腈一起顺利进行,在温和的条件下以中等至良好的收率得到相应的产物。此外,该反应方便地以克规模进行,产率仍高达68%。
RuCl3·3H2O Catalyzed Tandem Reaction of Alkynylbromides with 2-Aminothiophenols in Water: A Convenient Synthesis of 2-Benzoylbenzothiazoles
作者:Xuesen Fan、Yan He、Shenghai Guo、Xinying Zhang
DOI:10.1071/ch11217
日期:——
RuCl3·3H2Ocatalyzedtandemreaction of alkynyl bromides with 2-aminothiophenols mediated by water is shown to represent a convenient synthesis of 2-benzoylbenzothiazoles. In addition, the Ru(iii) catalyst could be readily recovered and efficiently reused together with water up to three times.
A multipathway coupled domino strategy has been developed for the efficient synthesis of 2-acylbenzothiazoles from multiform substrates arylethenes, arylacetylenes, 2-hydroxy-aromatic ketones, and carbinols via four distinct pathways. Through a logical coupled oxidation/heterocyclization domino process, a variety of 2-acylbenzothiazoles were synthesized free of metal in one pot.
A Sustainable Synthesis of 2-Benzoxazyl and 2-Benzothiazyl Ketones from Alkynyl Bromides and 2-Amino(thio)phenols Promoted by a Recyclable Catalytic System
作者:Liangyan Cui、Yan He、Xuesen Fan
DOI:10.1002/cjoc.201100472
日期:2012.4
An environmentally and economically sustainablesynthesis of 2‐benzoxazyl ketones and 2‐benzothiazyl ketones through FeCl3·6H2O catalyzed tandem reactions of alkynylbromides with 2‐amino(thio)phenols in [bmim]BF4 has been developed. Remarkable advantages of this new synthetic strategy include high efficiency, readily available starting materials, and recyclable catalyst and reaction medium.