Environmental benign synthesis of some novel biologically active 7-hydroxy-4-methyl coumarin derivatives

Abstract

In present work, some new 7-hydroxy-4-methyl coumarin derivatives have been synthesized by environmental benign and mechano-chemical methods and compounds were characterized by the data obtained from FT-IR, H1-NMR, C13-NMR and elemental analysis. Compounds I and its derivatives, III and VII were synthesized by mechanical grinding assisted Mannich reaction as well as conventional Mannich reaction while other compounds- II, IV, V, VI and VIII were synthesized without assistance of mechanical grinding. Fungicidal and herbicidal activities of all the synthesized compounds evaluated for selected species. All of these exhibited good fungicidal and insecticidal activities, specially compound VII and VIII are remarkably active. It was observed that assistance of mechanical grinding increases the yield of products in view of various parameters like-time, temperature, rotation per minute, reaction mass efficiency and atom economy which affect the yield and cost of product economy, mechanical grinding method is more significant as compared to conventional reflux methods.