Design and synthesis of bis-coumarinyl methanes from 4-hydroxy-coumarin and aldehydes catalysed by Amberlyst 15 via dual C–C coupling: introducing coumarin based thin film organic nano-materials for memory devices

Facile Synthesis of Bis‐Coumarins Using [BCMIM][Cl] Zwitter Ionic Liquid and Their Binding with Bovine Serum Albumin

“…Bis‐coumarin synthesis involves a Knoevenagel‐Michael addition, which is vital for generating C−C bonds in synthetic organic chemistry. A detailed review of the literature discloses the utilisation of numerous catalysts such as viologen‐based ionic porous organic polymer, [13] Amberlyst 15, [14] nanocatalysts, [15] Mohr's Salt, [16] ionic liquids, [15c,17] Aegle marmelos fruit ash, [18] carbon‐based acid catalyst, [2a] thiamine hydrochloride, [19] biosurfactants, [20] Meglumine, [21] trityl bromide, [22] Phosphotungstic acids, [23] melamine, [24] deep eutectic solvents (DES), [25] choline hydroxide, [26] and so on for the synthesis of biscoumarin. Although most of the stated methods are useful, yet holds several drawbacks, such as critical reaction conditions, expensive catalyst preparation process, low yields, longer reaction durations, and complex work‐up procedures.…”

Unsymmetrical Bis‐Coumarin Based on o‐Hydroxy Aldehydes and 4‐Hydroxy Coumarin: Expedient Synthesis, Single Crystal X‐rays and DFT Studies

“…Most of the reported methods rely on the involvement of a three component condensation of 4‐hydroxy coumarin ( 1 ) units and an aldehyde ( 2 ) through Knoevenagel condensation followed by Michael addition in the presence of various catalysts under room temperature or elevated temperature [5b,6b,15] . We have made efforts to synthesize bis‐coumarinyl methane's by the condensation of different aromatic and aliphatic aldehydes with 4‐hydroxy coumarin in water‐EtOH (1 : 1) solvent system in the presence of Amberlyst 15 as recyclable catalyst and explored their efficacy in fabrication of WORM memory device [16] . During the development of the synthetic protocol we have noticed that our strategy fails to produce expected symmetrical bis‐coumarin derivative when we have selected salicylaldehyde as one of the component since the said attempt only provide an inseparable mixture of solids.…”

“…[5b,6b,15] We have made efforts to synthesize bis-coumarinyl methane's by the condensation of different aromatic and aliphatic aldehydes with 4-hydroxy coumarin in water-EtOH (1 : 1) solvent system in the presence of Amberlyst 15 as recyclable catalyst and explored their efficacy in fabrication of WORM memory device. [16] During the development of the synthetic protocol we have noticed that our strategy fails to produce expected symmetrical bis-coumarin derivative when we have selected salicylaldehyde as one of the component since the said attempt only provide an inseparable mixture of solids. However, symmetrical bis-coumarinyl methane (4 a, R = H) using salicylaldehyde were explored by various research groups using different strategies [17][18][19][20][21][22][23][24][25][26][27][28] without any trouble.…”