An efficient and economical synthesis of 5-substituted 1H-tetrazoles via Pb(II) salt catalyzed [3+2] cycloaddition of nitriles and sodium azide
作者:Rama Kant、Vishal Singh、Alka Agarwal
DOI:10.1016/j.crci.2015.11.016
日期:2016.3
Résumé A simple, mild and efficient method is developed for the synthesis of 5-substituted 1H-tetrazoles. Out of three used Pb(II) catalysts, lead chloride (PbCl2) has been found to be an efficient catalyst for [3+2] cycloaddition of NaN3 with aromatic and aliphatic nitriles to afford 5-substituted 1H-tetrazoles. The catalyst is reusable up to four cycles with consistent activity. The cost effectiveness and easy availability of the catalyst, simple methodology, excellent yield and easy work-up are the additional advantages. Supplementary Materials: Supplementary material for this article is supplied as a separate file: mmc1.docx
An efficient one-pot, convenient catalysis for the synthesis of 5-substituted-1H-tetrazoles is reported. The [3+2] cycloaddition involves various nitriles, sodium azide in refluxing DMF and AgNO3 as catalyst to give corresponding 5-substituted-1H-tetrazoles in good to excellent yields. It is expected that the reaction proceeds via in situformation of a silver azide species, which participates in coordination
Silver nanoparticles (AgNPs), characterized by TEM, EDX and UV studies were used as an efficient heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles from various nitriles possessing different functional groups in excellent yields. All title compounds were characterized by spectroscopy (H-1 NMR, C-13 NMR and IR) and crystallography. (C) 2014 Published by Elsevier B.V.