Design and development of new methodology for the synthesis of lawsone based novel dihydropyrimidone dyes Their application on fabrics

Abstract

hypothesis describes the synthesis of novel dihydropyrimidone derivatives that have been paid attention to in organic, medicinal, dyes, and many other chemistry disciplines. The present work aims to develop a novel protocol for the synthesis of dispersed dyes derived via a triple cascade reaction. Here we have developed an efficient triple cascade protocol for the synthesis of novel disperses dyes with 3, 4- dihydro-2(H)-pyrimidinones/thione (DHPMs) scaffolds. These DHPMs derivatives were prepared by simple triple cascade Biginelli reaction via formal [1+2+3] cyclization by using various simple aromatic aldehydes, polynuclear carbaldehyde, heteroaryl carbaldehyde, urea/thiourea, and 2-hydroxy-1, 4-naphthoquinone (lawsone). Zinc acetate is used as an effective catalyst for this reaction. This process has varied substrate scope and shortened reaction duration with isolated yield for urea up to 98 % and for thiourea 95 % resulting in situ formation of one carbon carbon as well as two carbon nitrogen bonds. All newly prepared compounds were confirmed by FT-IR, 1H-NMR, 13C-NMR, and HRMS spectral analysis. The UV visible spectral analysis was also performed to study their intense depth of color with all the prepared molecules. All the newly synthesized dyes and lawsone were evaluated for their dyeing performance on nylon and polyester fabrics. The wash fastness, sublimation fastness, color assessment, determination of percentage exhaustion, and fixation properties were applied to both the dyed fabrics. The prepared novel dispersed dye greatly impacted their dyeing properties on nylon and polyester fibers. They have shown brilliant shades, higher affinity, higher adsorption capacity, and superior tinctorial strength than the lawsone. The percentage exhaustion value, fixation value, color strength (K/s) value, washing fastness, and sublimation fastness properties have been found very well in all dyed nylon samples compared to polyester samples. With the help of the commercialization of prepared molecules.