An iodine-catalyzed formation of substituted 2-aminobenzothiazole derivatives is herein described using hydrogen peroxide as an oxidant in PEG400. The method enabled an efficient environmentally sound access to this valuable scaffold in moderate to excellent yields under metal-free conditions.
Stereoselective Olefination and Regiospecific Vicinal Difunctionalization of Imines with α-(Benzothiazol-2-ylsulfonyl) Carbonyl Compounds
作者:You-Dong Shao、Xue-Song Wu、Shi-Kai Tian
DOI:10.1002/ejoc.201101684
日期:2012.3
Depending on their structures, imines are able to undergo either olefination or vicinal difunctionalization with various α-(benzothiazol-2-ylsulfonyl) carbonylcompounds in the absence of external bases. The olefination reaction of aromatic imines with α-(benzothiazol-2-ylsulfonyl) carbonylcompounds proceeds smoothly in tetrahydrofuran at 70 °C to give structurally diverse α,β-unsaturated esters,
amines and nucleobases have also been used, affording the corresponding coupling products in good to excellent yields. Moreover, this method has been employed for chemoselective C–N arylation of aminophenols and further utilized for the synthesis of carbazole natural products, avoiding the protection and deprotection steps.
Synthesis of Benz-Fused Azoles via C-Heteroatom Coupling Reactions Catalyzed by Cu(I) in the Presence of Glycosyltriazole Ligands
作者:Nidhi Mishra、Anoop S. Singh、Anand K. Agrahari、Sumit K. Singh、Mala Singh、Vinod K. Tiwari
DOI:10.1021/acscombsci.9b00004
日期:2019.5.13
and contain multiple metal-binding units that may assist in metal-mediated catalysis. Azide derivatives of d-glucose have been converted to their respective aryltriazoles and screened as ligands for the synthesis of 2-substituted benz-fused azoles and benzimidazoquinazolinones by Cu-catalyzed intramolecular Ullmann type C-heteroatom coupling. Good to excellent yields for a variety of benz-fused heterocyles
The synthesis of substituted benzimidazoles, 2-aminobenzimidazoles, 2-aminobenzothiazoles, and benzoxazoles is described via intramolecularcyclization of o-bromoaryl derivatives using copper(II) oxide nanoparticles in DMSO under air. The procedure is experimentally simple, general, efficient, and free from addition of external chelating ligands. It is a heterogeneous process and the copper(II) oxide