Silver-loaded TiO2 (Ag–TiO2) and acidic clay (K10 montmorillonite) composite photocatalyst has been successfully applied for the light-induced conversion of o-phenylenediamine (OPD) and its derivatives to substituted benzimidazoles with various alcohols in acetonitrile using UV-A and solar light. The influence of the various photocatalysts, solvents, and substituents on the yield and selectivity of the products has been investigated. The mechanism of photocatalysis is proposed. Loading silver on TiO2 enhances product yield and selectivity both in UV and solar light. In the presence of primary alcohols, 2-aminothiophenol forms only disulfide and hence Ag–TiO2/clay can be used as a green catalyst for the synthesis of disulfides.
developed an efficient method for the synthesis of benzimidazoles via cascade reactions of o-haloacetoanilide derivatives with amidine hydrochlorides. The protocol uses 10 mol % CuBr as the catalyst, Cs2CO3 as the base, and DMSO as the solvent, and no ligand is required. The procedure proceeds via the sequential coupling of o-haloacetoanilide derivatives with amidines, hydrolysis of the intermediates (amides)
Water-Mediated Synthesis of 2-Substituted Benzimidazoles by Boric Acid and Glycerol
作者:Chhanda Mukhopadhyay、Pradip Kumar Tapaswi、Ray J. Butcher
DOI:10.1071/ch08309
日期:——
A very simple, mild, and highly efficient green catalyst has been developed for the synthesis of 2-substituted benzimidazoles by treatment of substituted ortho-phenylenediamines and aldehydes in water at 80°C in the presence of boric acid (5 mol-%) and glycerol (0.05 mL). This methodology has been standardized on 55 substrates, and nine new compounds have been synthesized.
This invention relates to processes and intermediates for making compounds which are effective in inhibiting replication of Hepatitis C virus (HCV).
本发明涉及用于制造有效抑制丙型肝炎病毒(HCV)复制的化合物的工艺和中间体。
Water-soluble preflux, printed circuit board, and process for treating the surface of a metal in a printed circuit board
申请人:——
公开号:US20030141351A1
公开(公告)日:2003-07-31
The invention provides a water-soluble prefluxe that can solve problems with a soldering land array having a narrow spacing in that fused solder is likely to cause soldering bridges with defective soldering, a printed circuit board with its film formed thereon, and a surface treatment process for a metal in that circuit. The water-soluble preflus comprises given two different benzimidazoles compound and an iodine-based compound optionally with an amino acid, etc. The invention provides a printed circuit board with a film of that preflux formed thereon, and a surface treatment process for the metal in that circuit.