Application of nano SnO2 as a green and recyclable catalyst for the synthesis of 2-aryl or alkylbenzoxazole derivatives under ambient temperature
作者:SEYED MOHAMMAD VAHDAT、SHIMA GHAFOURI RAZ、SAEED BAGHERY
DOI:10.1007/s12039-013-0544-1
日期:2014.5
Application of nano SnO2 as an efficient and benign catalyst has been explored for the synthesis of 2-aryl or alkylbenzoxazole derivatives via condensation reaction of aldehyde with 2-aminophenol. The reactions proceed under heterogeneous and mild conditions in ethanol at room temperature to provide 2-aryl or alkylbenzoxazoles in high yields.
Highly efficient AgNO<sub>3</sub>
-catalyzed approach to 2-(benzo[<i>d</i>
]azol-2-yl)phenols from salicylaldehydes with 2-aminothiophenol, 2-aminophenol and benzene-1,2-diamine
derivatives in good to excellent yields (63–98%) is described. The reaction proceeds via condensation/intramolecular nucleophilic addition/oxidation process between substituted salicylaldehydes and 2‐aminothiophenol, 2‐aminophenol or benzene‐1,2‐diamine under mild reaction conditions. Notably, this reaction utilizes cheap AgNO3 as a readily available and low‐cost benign oxidant at low catalyst loadings with
描述了一种新的,便捷有效的AgNO 3催化策略,用于制备2-(苯并[ d ] azol-2-基)苯酚衍生物,产率高至优异(63-98%)。反应在温和的反应条件下通过取代的水杨醛与2-氨基硫酚,2-氨基酚或苯1,2-二胺之间的缩合/分子内亲核加成/氧化过程进行。值得注意的是,该反应利用廉价的AgNO 3作为易于获得的低成本良性氧化剂,催化剂负载低,具有出色的官能团耐受性。
Phenylboronic acid catalyzed-cyanide promoted, one-pot synthesis of 2-(2-hydroxyphenyl)benzoxazole derivatives
A novel, one-pot, phenylboronic acid catalyzed, cyanide promoted synthesis of 2-(2-hydroxyphenyl)benzoxazoles from salicylaldehydes and o-aminophenols is described. The synthesis is characterized by mild conditions, short reaction times, and simple workup of crystalline, high purity products. (C) 2011 Elsevier Ltd. All rights reserved.
Thermal cyclization of ? -nit ros o-?-naphthol, o-nitronaphthols, and o-nitrophenols with aromatic aldehydes
作者:E. Yu. Belyaev、L. E. Kondrat'eva、N. A. Shakhov
DOI:10.1007/bf00478478
日期:1972.1
An efficient potassium cyanide-promoted synthesis of 2-arylbenzoxazoles from [4.3.0]boron heterobicycles
The 2-arylbenzoxazoles 3a-f were produced in moderate to excellent yields merely by stirring a potassium cyanide (3 equiv)-containing methanol solution of the borobicyclic compounds 1a-f at room temperature. These compounds were fully characterized spectroscopically [1R, H-1, and C-13 NMR and X-ray analysis (3a)] and by elemental analysis. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.