Nouvelle Voie de Synthèse des 2-Arylbenzothiazoles Transfert d'Electrons Activé par Micro-ondes

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“…Alloum et al, have presented the condensation of various aldehydes with 2-aminothiophenol on silica gel / nitrobenzene or montmorillonite K-10 / nitrobenzene under microwave irradiation (MWI) which afforded 2-arylbenzothiazoles in good yields with high purity (Scheme 12, Method 4) 23 .…”

SnO2/SiO2Nanocomposite Catalyzed One-Pot Synthesis of 2-Arylbenzothiazole Derivatives

“…The most commonly used method involves the condensation of 2-aminothiophenol with substituted nitriles, carboxylic acids, aldehydes, acyl chlorides or esters. 41 49 However, some of these methods are plagued by one or many drawbacks such as long reaction time, use of volatile solvents, low yields and harsh reaction conditions etc. Therefore, it is still necessary to develop an improved route for the synthesis of benzothiazoles under mild reaction conditions.…”

Solid-Phase Synthesis of 2-Arylbenzothiazole Using Silica Sulfuric Acid under Microwave Irradiation

“…In addition, they represent one of the most promising antiamyloid therapies for treatment of a number of a heterogeneous family of diseases referred to generically as amyloidosis, including Alzheimer's disease (AD), type II diabetes, variant Creutzfeldt-Jakob disease, painful joints associated with long term hemodialysis and rare cases of hereditary insomnia. 5,6 In general, benzothiazoles are synthesized by condensation of 2-aminothiophenol with carboxylic acid derivatives, 7 the base induced cyclization of the corresponding 2 haloanilides, 8 or the radical cyclization of thioacylbenzanilides. 9 On the other hand, the most general synthetic approaches for 2-aryl benzothiazoles involves: (i) arylation of benzothiazole with aryl bromides at 150 ο C in a sealed tube catalyzed by Pd(OAc)2, Cs2CO3 and CuBr with t-Bu 3 P as ligand, 10 or Suzuki biaryl-coupling of 2-bromobenzothiazole with aryl boronic acids, 11 (ii) oxidative cyclisation of phenolic Schiff's bases derived from the condensation of 2-aminothiophenols and aldehydes using various oxidants such as Sc(OTf)3 using molecular oxygen, 12 pyridinium chlorochromate 13 and very recently via electrooxidation, 14 a modification of such strategy that involves flash vacuum pyrolysis and photolysis of 2-methylthio-N (arenylidene)anilines has been reported, 15 (iii) condensation of 2-aminothiophenols with carboxylic acids under microwave irradiation 16 or with polymer-bound esters in the presence of a Lewis acid, 17 (iv) direct condensation of 2-aminothiophenol with aromatic aldehydes, 18,19 under microwave-irradiation.…”