ZnO-NPs catalyzed condensation of 2-aminothiophenol and aryl/alkyl nitriles: Efficient green synthesis of 2-substituted benzothiazoles

Copper-Mediated Cyanodifluoromethylation of (Hetero)aryl Iodides and Activated (Hetero)aryl Bromides with TMSCF2CN

“…The addition of thiols or hydroxylamines to arylacetonitriles typically requires forcing conditions or an acid catalyst, and no product was observed from reactions of benzyl nitrile with these two reagents under conditions for reactions of 5b and 5c . The reduction of arylacetonitriles lacking fluorine substitution at the benzylic position also often requires high temperatures or catalysts to proceed; the addition of LAH to benzyl nitrile under analogous conditions for 5d formed no reduced product. , Cyclization reactions to form products analogous to benzothiazole 5i without fluorine atoms did not proceed under analogous conditions, even with the addition of AlCl 3 as Lewis acid. − We ascribe the demonstrated difference in reactivity between aryldifluoroacetonitriles and arylacetonitriles to the inductive effect of the fluorine atoms adjacent to the nitrile carbon.…”

Triazine diphosphonium tetrachloroferrate ionic liquid immobilized on functionalized halloysite nanotubes as an efficient and reusable catalyst for the synthesis of mono-, bis- and tris-benzothiazoles

“…FT-IR spectra was recorded on a Jasco 6300 in the range of 400-4000 cm −1 . 1 H and 13 C NMR (400 and 100 MHz) spectra were recorded on a Bruker Avance 400 MHz spectrometer using DMSO-d 6 and CDCl 3 as solvent. Elemental analysis was performed on a LECO, CHNS-932 analyzer.…”

“…For instance, it was reported that benzothiazoles skeletons could be obtained through the condensation of 2-aminothiophenol and aryl/alkyl nitriles using ZnO-nanoparticles as a catalyst. 13 The reaction of 2-aminothiophenol with orthoesters in the presence of catalytic amounts of Bi(III) salts, has been also reported for the synthesis of benzothiazoles under solvent-free conditions. 14 This structure could also be generated from ophenylenediamine and N-substituted formamides (C1 sources) via a one-pot protocol catalyzed by zinc in the presence of poly(methylhydrosiloxane).…”

Synthesis of 2-trifluoromethyl benzimidazoles, benzoxazoles, and benzothiazoles via condensation of diamines or amino(thio)phenols with CF3CN

“…29 Also, we have recently demonstrated new efficient protocols for assembling a range of novel five-membered nitrogen-containing heterocycles using in situ generated trifluoroacetonitrile from 2,2,2-trifluoroacetaldehyde O-(aryl)oxime. [30][31][32][33] On the basis of these previous studies, especially on the synthesis of benzothiazoles and their structural analogues by the condensation of 2-aminothiophenol and nitriles, [34][35][36] and our continued interest in trifluoromethylated heterocycle synthesis, [37][38][39][40][41] we further became interested in designing efficient methodologies for the synthesis of 2-trifluoromethyl benzimidazoles and benzothiazoles via condensation of diamines or amino(thio)phenols with CF 3 CN (Scheme 1b).…”