Microwave assisted one-pot synthesis of pyrazoloquinazolinone derivatives and their application on printing of synthetic fabrics

Abstract

Purpose – The purpose of this paper is to synthesize some novel 2-amino-6,6-dimethyl-9-phenyl-3-(phenyldiazenyl)-6,7-dihydropyrazolo-[5,1-b]quinazolin-8(5H)-one derivatives by multi-component one-pot reaction using a microwave as a new tool for green chemistry. Design/methodology/approach – An equimolor from arylazopyrazole, 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and benzaldehyde derivatives was dissolved in Dimethylformamide (DMF) to be irradiated in a microwave for 15 minutes; after completion of the reaction, as indicated by Thin layer chromatograph (TLC), the reaction mixture was poured into ice water, filtered and then crystallized with an appropriate solvent. Findings – The structure of the synthesized dyes was established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and 1H-NMR). These prepared dyes were used to print polyester and polyamide fabrics using synthetic thickener in the printing paste for the silk screen technique. The synthesized dyes are superior in terms of yield, purity, color strength and fastness properties and will lead to valuable achievements for commercial production. Originality/value – An efficient method for synthesis of pyrazoloquinazolinone dyes was designed. The novel procedure features short reaction time, moderate yields and simple workup. The authors studied its application in printing polyester and polyamide fabrics.