L-Proline based ionic liquid: A highly efficient and homogenous catalyst for synthesis of 5-benzylidene-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione and pyrano[2,3-d] pyrimidine diones under ultrasonic irradiation

Recent advancements in the multicomponent synthesis of heterocycles integrated with a pyrano[2,3-d]pyrimidine core

“… 83 In addition, another performance was described by Mohamadpour, 84 for the synthesis of bicyclic pyranopyrimidines with an enaminonitrile moiety using visible light irradiation in a green protocol. Patila et al 85 synthesized a series of pyranopyrimidine-diones 20a–k using l -proline-based ionic liquid as an efficacious catalyst. Thus, l -proline-NO 3 catalyzed one-pot multicomponent reactions of aryl aldehydes with malononitrile and N , N -dimethyl-barbituric acid under either conventional (80 °C) or ultra-sonication conditions to furnish the anticipated pyranopyrimidines 20a–k ( Scheme 12 ).…”

Ultrasound-assisted transition-metal-free catalysis: a sustainable route towards the synthesis of bioactive heterocycles

“…Another great achievement for the utilization of ultrasound irradiation in the construction of complex-fused heterocycles by introducing l -proline-based ionic liquids as the efficient homogeneous catalyst was disclosed by More et al at the same time ( Scheme 48 ). 196 Initially, the ionic liquid l -proline-NO 3 was prepared by the authors from the reaction of l -proline with HNO 3 in water at 60 °C for 24 hours. After the successful formation of the catalyst, a three-component reaction between aryl/heteroaryl aldehydes 23, malononitrile 96, and 1,3-dimethyl barbituric acid 164 in water was executed using both traditional heating and ultrasonication to examine the catalytic activity of the prepared catalyst.…”

L-Proline-Based Natural Deep Eutectic Solvents as Efficient Solvents and Catalysts for the Ultrasound-Assisted Synthesis of Aurones via Knoevenagel Condensation

“…Moreover, proline-based ionic liquids can be successfully applied as solve basic catalysts for a Michael addition reaction between chalcone and dimethyl ma as shown in the work of Bacha et al [14]. Proline nitrate, another proline-based io uid, was recently reported to effectively catalyze the synthesis of pyrimidine deri in various solvents, as well as in H2O [15].…”