Triethanolamine as an inexpensive and efficient catalyst for the green synthesis of novel 1H-pyrazolo[1,2-a]pyridazine-5,8-diones under ultrasound irradiation in water and their antibacterial activity

Abstract

Triethanolamine was found to be an efficient catalyst for the synthesis of new 1H-pyrazolo[1,2-a] pyridazine-5,8-diones by a one-pot reaction of maleic hydrazide, with aromatic aldehydes and malononitrile in H 2 O under ultrasonic irradiation. The advantages of this method are the use of an inexpensive and readily available catalyst, easy workup, improved yields, and the use of H 2 O as a green solvent. To assess their antibacterial activity, all the synthesized compounds were dissolved in DMSO and subjected to biological evaluation using the disc diffusion method against 3 Gram positive and 3 Gram negative bacteria.

Triethanolamine‐catalyzed expeditious and greener synthesis of 2‐amino‐4H‐chromenes

“…The structure of the product 4a was confirmed by comparison of the melting points and through thin‐layer chromatography (TLC) with an authentic sample prepared by following a reported method and also by spectral data (IR, mass spectrometry, and 1 H NMR).…”

“…Triethanolamine (TEOA) has been utilized as surfactant and an emulsifier in many consumer products such as detergents, dishwashing, hand cleaners, polishes, paints, shaving creams, and printing inks . Recent reports have demonstrated the efficiency of TEOA as catalyst in several organic transformations including phosphate‐free Heck reactions, and Knoevenagel‐type cyclocondensation, and as a reusable reaction medium for the synthesis of aryl sulfones . From the green chemistry perspective, we hoped that replacing conventional organic bases (TEA, piperidine, or pyridine) with TEOA in water can be an effective strategy for the synthesis of 2‐amino‐4 H ‐chromenes.…”

An Experimental and Theoretical Study on the Unexpected Catalytic Activity of Triethanolamine for the Carboxylative Cyclization of Propargylic Amines with CO2

“…[32][33][34] As earlya s1 931, alkanolamines were utilized to capture carbon dioxide from natural gas. [32][33][34] As earlya s1 931, alkanolamines were utilized to capture carbon dioxide from natural gas.…”

“…As ac lass of low-costa nd biodegradable bases,a lkanolamines have been used in aw idev arietyo fi ndustrially important processes such as natural gas stripping, adhesives, acid neutralization, paint stripping, surfactants, and derivatives in drug formulations. [32][33][34] As earlya s1 931, alkanolamines were utilized to capture carbon dioxide from natural gas. [35] This gave us inspiration:m aybe alkanolamines can strongly activate CO 2 in the CO 2 conversion process.…”

Preparation and characterization of nanomagnetic piperidinium benzene‐1,3‐disulfonate ionic liquid as a novel, green and heterogeneous catalyst and its use in the synthesis of 1H–pyrazolo[1,2‐b]phthalazine‐5,10‐diones and 1H–pyrazolo[1,2‐a] pyridazine‐5,8‐diones under solvent‐free conditions

“…The synthesis of 1 H –pyrazolo[1,2‐ b ]phthalazine‐5,10‐diones and 1 H –pyrazolo[1,2‐ a ]pyridazine‐5,8‐diones has attracted a great deal of attention because of their biological and pharmacological actions. Literature reports have already established that pyrazoles and phthalazines have various pharmacological properties such as anticancer, antifungal anti‐inflammatory, antiviral, antidepressant, antibacterial, antipyretic and anticonvulsant activities. In this paper we present a new class of ionic liquid, namely piperidinium benzene‐1,3‐disulfonate nanomagnetic ionic liquid (NMIL; Scheme ), as a simple, efficient and novel catalyst, which was successfully used as a catalyst in the solvent‐free synthesis of 1 H –pyrazolo[1,2‐ b ]phthalazine‐5,10‐diones and 1 H –pyrazolo[1,2‐ a ]pyridazine‐5,8‐diones via the one‐pot four‐component condensation reaction between various aldehydes, malononitrile, hydrazine hydrate and phthalic anhydride or maleic anhydride (Scheme ).…”