Solid acid catalyst and method for catalytic synthesis of 5-substituted tetrazole by solid acid catalyst

Abstract

The invention discloses a solid acid catalyst, which is characterized by taking bisulfate as an active ingredient and SiO2, ZnO, TiO2, ZrO2, Fe2O3, diatomite or active carbon as a carrier, wherein the loading amount of the active ingredients of the solid acid catalyst is 5 to 50wt%; and the bisulfate is ammonium bisulfate, sodium bisulfate or potassium bisulfate; the method of solid acid for the catalytic synthesis of 5-substituted tetrazole comprises the steps of: using nitrile compound and sodium azide as raw material and solid acid as catalyst, reacting for 8 to 72 hours in organic solvent at 120 to 160 DEG C, post-treating the reaction liquid to obtain the 5-substituted tetrazole; the solid acid catalyst of the invention has the advantages of moderate application conditions, high activity, simple preparation and no environmental pollution; and the process of the invention for synthesizing the 5-substituted tetrazole is simple and safe, easy in operation, high in yield, environmentally-friendly and suitable for industrial production.

Description

(1) Technical field [0001] The invention relates to a method for synthesizing 5-substituted tetrazole, in particular to a method for catalyzing and synthesizing 5-substituted tetrazole with a solid acid catalyst. (2) Background technology [0002] Tetrazolium compounds are important intermediates in organic synthesis, which can be used to synthesize medicines, pesticides, photosensitive materials and industrial foaming agents and other products. 5-Substituted tetrazole has significant biological activity and is often used in the modification of cephalosporin antibiotics, angiotensin receptor inhibitors and anti-tumor drugs. In recent years, tetrazole compounds have been used more and more in the field of medicine. More and more, and has a good development prospect. [0003] The synthetic method of 5-substituted tetrazole has a lot, utilizes nitrile compound and sodium azide to make tetrazole under the condition that alcohol (such as n-butanol, Virahol) is made solvent, acid...

AI Technical Summary

Problems solved by technology

[0003] The synthetic method of 5-substituted tetrazole has a lot, utilizes nitrile compound and sodium azide to make tetrazole under the condition that alcohol (such as n-butanol, Virahol) is made solvent, acid (such as glacial acetic acid) is made catalyst. Azole compounds are the most classic method, but this method is only suitable for the synthesis of simple tetrazole

Change the solvent to an aprotic solvent (such as DMF, DMAC), use an inorganic salt or an organic salt (such as NH 4 Cl, ZnCl 2 、Et 3 N HCl) as catalyzer, nitrile compound and sodium azide reaction can prepare tetrazole derivatives with aromatic group with complex structure, but same as above-mentioned reaction, this reaction speed is slower, and the reaction time is long ( It takes a few days), and it is easy to produce toxic and explosive HN 3 , NH 4 N 3 Wait

There are also reports in the literature that organotin catalysis is used to synthesize tetrazole derivatives containing multifunctional groups in aromatic hydrocarbon solvents, but there are many by-products, the target product is difficult to completely separate, the yield is low, the post-treatment is cumbersome, and the price of tin compounds is high. Toxic