A Practical Oxone®-Mediated,High-Throughput, Solution-Phase Synthesis of Benzimidazolesfrom 1,2-Phenylenediamines and Aldehydes and its Application toPreparative Scale Synthesis
A Practical Oxone®-Mediated,High-Throughput, Solution-Phase Synthesis of Benzimidazolesfrom 1,2-Phenylenediamines and Aldehydes and its Application toPreparative Scale Synthesis
Continuous-Flow Synthesis of 1<i>-</i>Substituted Benzotriazoles from Chloronitrobenzenes and Amines in a CN Bond Formation/Hydrogenation/Diazotization/Cyclization Sequence
作者:Mao Chen、Stephen L. Buchwald
DOI:10.1002/anie.201300615
日期:2013.4.8
Two approaches have been developed for the regiospecific continuous‐flow synthesis of 1‐substituted benzotriazoles. They begin with either an SNAr reaction at high temperature or Pd catalysis and involve consecutive multiphase processes, allowing the multistep synthesis of benzotriazoles to take place in an efficient manner (see picture).
已经开发出两种方法用于1-取代的苯并三唑的区域特异性连续流动合成。它们从高温下的S N Ar反应或Pd催化开始,并且涉及连续的多相过程,从而可以高效地进行苯并三唑的多步合成(见图)。
A Practical Oxone®-Mediated,High-Throughput, Solution-Phase Synthesis of Benzimidazolesfrom 1,2-Phenylenediamines and Aldehydes and its Application toPreparative Scale Synthesis
作者:Pierre Beaulieu、Bruno Haché、Elisabeth von Moos
DOI:10.1055/s-2003-40888
日期:2003.8
Addition of oxone® to a mixture of a 1,2-phenylenediamine and an aldehyde in wet DMF at room temperature results in rapid formation of benzimidazoles under very mild conditions. The reaction is applicable to a wide range of substrates including aliphatic, aromatic and heteroaromatic aldehydes, and is not significantly affected by steric or electronic effects. In most cases, crude products are isolated in good to excellent yields (59-95%) and homogeneities (86-99%) by simple precipitation or extraction from the reaction mixture and do not require additional purification. Limitations to the scope of this methodology were encountered in cases where aldehydes were sensitive to oxone® under the acidic reaction conditions. The features of this methodology make it particularly well suited for the high-throughput, solution-phase synthesis of benzimidazole libraries. The low cost and simplicity of this procedure makes it equally attractive for preparative-scale syntheses where safety and environmental issues are of greater concern.