Water Extract of Onion Peel Ash: An Efficient Green Catalytic System for the Synthesis of Isoindoline-1,3-Dione Derivatives

Abstract

Isoindoline-1,3-dione derivatives are important organic compounds associated with various interesting applications such as in the fields of material science, medicine, important building blocks and so on. Traditionally, the synthesis of isoindoline-1,3-dione derivatives are achieved using harmful and toxic catalysts, such as concentrated sulphuric acid, triphenylphosphine, ionic liquid [bmim][BF 4 ] or phthalimide-N-sulfonic acid. Thus, the development of a greener catalytic system for the synthesis of isoindoline-1,3-dione derivatives is highly sought after. In this work, an efficient synthesis of isoindoline-1,3-dione derivatives using the Water Extract of Onion Peel Ash (WEOPA) method is described. The new approach provides several advantages including the non-usage of external acids, recyclable catalytic system, cheap and the yield of the synthesized products were obtained in moderate to good yields by reacting various anilines with phthalic anhydride. The current improved method is scientifically important, due to it avoid the use of environmental harmful reagents and at the same time provides an alternative method for bio-waste management.

Phthalic anhydride (PA): a valuable substrate in organic transformations

“…Chia group in 2019 prepared the isoindoline-1,3-diones via the reaction of anilines and PA in the presence of “water extract of onion peel ash” (WEOPA) (2 mL) as a green catalytic-solvent system at 80 °C within 8 min by 64–92%. 109 The WEOPA was recycled and reused for 5 runs without significant activity loss.…”

“…Phthalimide derived from benzylamine exhibited remarkable antimicrobial activity against E. coli . 109 …”