Radical synthesis of dihydropyrano[2,3‐c]pyrazoles using acridine yellow G as a photo‐induced electron transfer photocatalyst

Abstract

AbstractWe developed a green method for the synthesis of dihydropyrano[2,3‐c]pyrazole scaffolds using Knoevenagel‐Michael tandem cyclocondensation of ethyl acetoacetate, hydrazine hydrate, aldehydes, and malononitrile. Acridine yellow G (AYG) was used as a photo‐induced electron transfer (photo‐induced electron transfer) photocatalyst via visible light as a sustainable energy source in an aqueous solution. This study is aimed at the development of an inexpensive and readily available non‐metal dye. With photochemically catalyzed AYG, yields are high, energy efficiency and environmental friendliness are present, as are significant atom economies, speed‐saving features, and ease of use. The result is that a wide range of chemical and environmental variables can be monitored over time. In this study, we calculated the turnover number (TON) and turnover frequency (TOF) of dihydropyrano[2,3‐c]pyrazole scaffolds.