Highly Atom-Economic, Catalyst-Free, and Solvent-Free Synthesis of Phthalazinones

Abstract

Herein a simple, catalyst- and solvent-free system for highly atom-economic synthesis of phthalazinones has been developed using phthalaldehydic acid, 2-acyl-benzoic acid, and substituted hydrazine as simple substrates. The reaction time was shortened to 20–60 min. Structurally diverse phthalaldehydic acids, 2-acyl-benzoic acids, and hydrazines were transformed into phthalazinones with a nearly 100% yield regardless of the aggregate state and electronic nature of the substituents. The transformation was demonstrated to be amenable for scale-up with multiple liquid and solid materials. In addition, isolation and purification of the crude products can be simply done with only crystallization. The heavy metal pollution was also eliminated from the source.

Synthesis of isoeugenol biobased epoxy polymer by forming α‐hydroxyl ester and degradation studies

“…An additional important factor is atom economy, 33 and is one of the fundamental principles of green chemistry; minimizing the product waste is essential to obtain a high atom economy 34 . Considerable efforts have been directed toward the development of new chemical transformations with high atom economy 35 .…”

Reagent-free intramolecular hydrofunctionalization: a regioselective 6-endo-dig cyclization of o-alkynoylphenols

“…This includes reduction of costs, energy usage, material consumption, wastes, hazards, risks, and usage of non-renewable resources. 1,2 Hence, the replacement or avoidance of hazardous catalysts, additives, and solvents has been considered by academia and industry over the past few decades. 1,3 Typically, catalysts and additives are utilized to accelerate chemical reactions and improve yields.…”

“…1,2 Hence, the replacement or avoidance of hazardous catalysts, additives, and solvents has been considered by academia and industry over the past few decades. 1,3 Typically, catalysts and additives are utilized to accelerate chemical reactions and improve yields. However, these are often expensive, toxic, and environmental pollutants.…”

Synthesis of Pyridine Derivatives from Acetophenone and Ammonium Acetate by Releasing CH4

“…Furthermore, reactions of neat reactants without solvent can eliminate lethal heavy solvent pollution from the source and enhance the purity of products, which is a desired solution for synthesis of active pharmaceutical ingredients (APIs) and biologicals. [10] In the past few years, our group has reported plenty of methods for the synthesis pyridines. For examples, in 2016, our group developed copper-catalyzed synthesis of pyridines via oxidative sp 3 CÀ H coupling of oxime acetates with toluene derivatives (Scheme 1a).…”