Ultrasound-promoted one-pot three component synthesis of tetrazoles catalyzed by zinc sulfide nanoparticles as a recyclable heterogeneous catalyst

Abstract

Ultrasound irradiation was applied for the appropriate and rapid synthesis of 1-substituted tetrazoles through cyclization reaction of various primary amines, sodium azide and triethyl orthoformate. This reaction was effectively catalyzed by ZnS nanoparticles as an efficient, recoverable and reusable catalyst. Compared with conventional methods, this method has the considerable advantages such as shorter reaction times, easier work-up, purer products with high yields and mild conditions. The ZnS nanoparticles catalyst is an excellent instance to replace Brønsted acids for the preparation of 1-substituted tetrazole derivatives in very short reaction times with excellent yields. The catalyst can be recovered and reused several times without significant loss of its catalytic activity.

First report of the direct supporting of palladium–arginine complex on boehmite nanoparticles and application in the synthesis of 5‐substituted tetrazoles

“…Tetrazoles can be used as isosteric replacements for carboxylic acids in drug design and have found use in various material sciences, including photography and information recording systems . Also, tetrazoles and their derivatives have been reported as analgesic, antifungal, anti‐inflammatory, antibacterial, antiviral and anti‐proliferative agents, potential anti‐HIV drug candidates and herbicidal and anticancer agents . Valsartan and losartan are two typical examples of the extensive application of these compounds in drugs, such as antihypertensive sartan family drugs .…”

Efficient synthesis of 5‐substituted tetrazoles catalysed by palladium–S‐methylisothiourea complex supported on boehmite nanoparticles

“…Also, recently tetrazole derivatives were used for binding aryl thiotetrazolylacetanilides with HIV‐1 reverse transcriptase . Tetrazoles and their derivatives have been reported as anti‐viral, anti‐bacterial, anti‐inflammatory and herbicidal agents, potential anti‐HIV drug candidates and anti‐proliferative, analgesic and anti‐tumour agents . Tetrazoles can be used as isosteric replacements for carboxylic acids in drug design and have found use in information recording systems …”

Ultrasound and Nano‐Catalysts: An Ideal and Sustainable Combination to Carry out Diverse Organic Transformations

“…A series of 1‐substituted tetrazoles ( 59 ) was synthesized via ultrasound‐assisted nano‐ZnS catalyzed one‐pot three‐component reactions of various aromatic primary amines ( 7 ), triethyl orthoformate ( 57 ) and sodium azide ( 58 ) in dimethyl formamide (DMF) at room temperature (Table ) . In absence of ultrasound, i. e ., under conventional stirring conditions the same reaction (Scheme 29, entry 1) afforded only 12% yield of the desired product after two hours.…”