Synthesis of arylaminotetrazoles by ZnCl2/AlCl3/silica as an efficient heterogeneous catalyst

Abstract

Arylaminotetrazoles were efficiently synthesized from secondary arylcyanamides by application of ZnCl 2 /AlCl 3 /silica as a reusable heterogeneous Lewis acid catalyst. 5-Arylamino-1H-tetrazoles can be obtained from arylcyanamides carrying electron-withdrawing substituents on the aryl ring, while with electron-releasing groups 1-aryl-5-amino-1H-tetrazoles will be produced. The former isomer is also produced within longer reaction times (*20 h) even with electron-releasing groups.

Application of the Fe3O4@1,10‐phenanthroline‐5,6‐diol@Mn nano‐catalyst for the green synthesis of tetrazoles and its biological performance

“…Since the early 1980s, tetrazoles have been of great interest because of their therapeutic applications . The tetrazole moiety is present in compounds possessing pharmacological properties, such as antihypertensive, anti‐allergic and antibiotic activity . In addition, they also have widespread use in coordination chemistry, imaging technology, agriculture and manufacturing of explosive materials .…”

CoFe2O4 Nanoparticles as a Magnetically Recoverable and Reusable Catalyst for the Synthesis of Arylaminotetrazoles and 5-aryloxytetrazoles

“…FeCl 3 -SiO 2 13 and glacial HOAc 7 catalysts gave a mixture of isomers (A + B), while nano CoFe 2 O 4 gave just the isomer (A). Another method needed 0.4 g of zinc (II) chloride as reagent under reflux in water and involved long reaction times (15 h).…”

“…DMF is a suitable solvent for these cycloaddition reactions. 13,14 The optimum amount of nano CoFe 2 O 4 was found to be 0.1 g in the presence of cyanamides (2 mmol) and sodium azide (3 mmol) in DMF (6 mL). We next examined a variety of structurally divergent phenylcyanamide possessing a wide range of functional groups to understand Table 2.…”

“…A similar mechanism has been reported for the synthesis of arylaminotetrazoles using catalyst ZAS. 13 The reactivity of several cyanates was also tested in the reaction with sodium azide in the presence of nano CoFe 2 O 4 under thermal conditions. The results are given in Table 3.…”

Copper Complex-catalysed C–N Coupling Reaction of Aryl Iodides with Nitrogen-containing Heterocycles

“…[1][2][3][4][5][6][7][8][9][10] The classical approaches to the syntheses of compounds bearing an arylated nitrogen moiety [11][12][13][14][15] are based on the aromatic nucleophilic substitution reaction (S N Ar) by nitrogen nucleophiles of activated aryl halides or alternatively the classical Ullmann 16,17 coupling at higher temperature. [1][2][3][4][5][6][7][8][9][10] The classical approaches to the syntheses of compounds bearing an arylated nitrogen moiety [11][12][13][14][15] are based on the aromatic nucleophilic substitution reaction (S N Ar) by nitrogen nucleophiles of activated aryl halides or alternatively the classical Ullmann 16,17 coupling at higher temperature.…”