Catalytic synthesis of benzoxanthene derivatives by acidic bifunctional ionic liquids

Abstract

The invention discloses an acidic bifunctional ionic liquid catalysis method for synthesis of benzoxanthene derivatives. The key points of the technical scheme provided by the invention are as below: the acidic bifunctional ionic liquid catalysis method for synthesis of the benzoxanthene derivative employ aromatic aldehyde and 2-naphthol as raw materials and employs the acidic bifunctional ionic liquid comprising cation containing hydrogen bond donor and Bronsted acidic anion as the catalyst, and the raw materials and the catalyst are heated to 110-125 DEG C at atmospheric pressure to synthesize the benzoxanthene derivative. The invention adopts the bifunctional acidic ionic liquid as the catalyst; the materials have wide sources and are simple for preparation and low in cost; the catalyst has low dosage, high catalytic activity, and can be recycled; and the reaction process can be performed under solvent-free conditions to avoid the use of organic solvents, so as to achieve environmental and economical double benefits. The method for the synthesis of the benzoxanthene derivatives is efficient, environmentally friendly, and conducive to large-scale industrial production.

Description

technical field [0001] The invention belongs to the technical field of synthesis of benzoxanthene derivatives, in particular to a method for catalytically synthesizing benzoxanthene derivatives with an acidic bifunctional ionic liquid. Background technique [0002] Xanthenes, especially benzoxanthene compounds, occupy a very important position in chemical organic synthesis because of their wide therapeutic range and pharmacological properties, such as antiviral drugs, antibacterial agents, anti-inflammatory drugs, antagonists etc., and it also shows good application in the field of laser technology as a photosensitive material. There have been many reports describing different methods for the synthesis of benzoxanthene derivatives, including the reaction of β-naphthol with formamide, CO, the reaction of β-naphthol with acetal, and the reaction of β-naphthol with 2-naphthalene The reaction of phenol-1-methanol, etc. It has been reported recently that benzoxanthenes are synt...

AI Technical Summary

Problems solved by technology

Acidic ionic liquids with hydroxyl groups on the cation have high thermal stability, and have shown good applications in acid-catalyzed Biginilli reactions and Pechemann reactions, but their applications in the catalytic synthesis of benzoxanthene derivatives have not been reported.