Straightforward synthesis of benzoxazoles and benzothiazoles via photocatalytic radical cyclization of 2-substituted anilines with aldehydes
作者:Hao Anh Nguyen Le、Long Hoang Nguyen、Quynh Nhu Ba Nguyen、Hai Truong Nguyen、Khang Quoc Nguyen、Phuong Hoang Tran
DOI:10.1016/j.catcom.2020.106120
日期:2020.10
Eosin Y-catalyzed one-pot coupling and cyclization of o-substituted anilines with aldehydes to form benzoxazoles and benzothiazoles under mild condition has been developed. The reaction scope was broadly tolerant of various 2-substituted anilines and aldehydes. The desired products were obtained in high yields with the use of eosin Y as a photocatalyst under a substantial refinement of reaction conditions
Deep eutectic solvent-catalyzed arylation of benzoxazoles with aromatic aldehydes
作者:Phuong Hoang Tran、Anh-Hung Thi Hang
DOI:10.1039/c8ra01094c
日期:——
A novel and efficient methodology for the arylation of benzoxazoles with aromaticaldehydes catalyzed by deep eutectic solvent has been developed. The reaction smoothly proceeded with a wide range of substrates to give the desired products in high yields within short reaction time. Deep eutectic solvents are easily recovered and reused without significant loss of catalytic activity.
Iron(III) Chloride Mediated
<i>para</i>
‐Selective C‐H Functionalization: Access to C5‐Chloro and C5,C7‐Dichloro/Dianisyl Substituted 2‐Arylbenzoxazoles
作者:Kanchanbala Sahoo、Niranjan Panda
DOI:10.1002/adsc.202101359
日期:2022.3
Iron(III) chloride mediated para-selective C−H chlorination and subsequent annulation of 2-amidophenol to synthesize C5- and C5, C7-chlorinated benzoxazoles was developed. Further, the oxidative cross-dehydrogenative coupling of amidophenol with anisole by ferricchloride was explored to achieve the remotely anisylated benzoxazoles.
Phosphonium acidic ionic liquid: an efficient and recyclable homogeneous catalyst for the synthesis of 2-arylbenzoxazoles, 2-arylbenzimidazoles, and 2-arylbenzothiazoles
作者:Quang The Nguyen、Anh-Hung Thi Hang、Thuy-Linh Ho Nguyen、Duy-Khiem Nguyen Chau、Phuong Hoang Tran
DOI:10.1039/c8ra01709c
日期:——
A highly efficient and green strategy for the synthesis of 2-arylbenzoxazoles, 2-arylbenzimidazoles, and 2-arylbenzothiazoles catalyzed by phosphonium acidic ionic liquid has been developed via the condensation of o-aminophenol, o-phenylenediamines, and o-aminothiophenol, respectively, with aldehydes. The reaction has a good yield, the broad substrate scope, and mild condition. Triphenyl(butyl-3-s
分别通过邻氨基苯酚、邻苯二胺和邻氨基苯硫酚的缩合,开发了一种由鏻酸性离子液体催化合成 2-芳基苯并恶唑、2-芳基苯并咪唑和 2-芳基苯并噻唑的高效绿色策略,与醛。该反应收率好,底物范围广,条件温和。三苯基(丁基-3-磺酰基)鏻甲苯磺酸盐催化剂通过一锅法合成很容易从廉价且可用的起始材料中获得。其结构经1 H NMR、13 C NMR、31P NMR和FT-IR技术。热稳定性和酸度等其他性质采用TGA和Hammett酸度函数法测定。有趣的是,催化剂在第四次复苏之前仍能保持其持续的出色表现。
Sulfur/DABCO Promoted Reductive Coupling/Annulation Cascade Reaction between o-Hydroxy/Amino Nitrobenzenes and Benzaldehydes
作者:Phuong Hoang Tran、Minh-Huy Dinh Dang、Linh Ho Thuy Nguyen
DOI:10.1055/s-0039-1690823
日期:2020.6
Sulfur/DABCO was found to be an efficient reagent in promoting the reductivecoupling/annulation of o-nitrophenols or o-nitroanilines with benzaldehydes. This method represents a simple, straightforward, and green approach to the construction of benzoxazoles and benzimidazoles.