[bmim]OH: An efficient catalyst for the synthesis of mono and bis spirooxindole derivatives in ethanol at room temperature

Engaging Isatins in Multicomponent Reactions (MCRs) – Easy Access to Structural Diversity

“…The [bmim]OH catalyst mediates the Knoevenagel and Michael‐Addition reactions, with the hydroxyl group playing an important role in the reactions, as in the first reaction it will deprotonate the malononitrile, while the hydrogen from the imidazolium will activate the C‐3 carbonyl from isatin forming the Knoevenagel adduct. In the case of the Michael addition the hydroxyl group will catch the proton from the active methylene group, furnishing the intermediate for the reaction [103] …”

Recent applications of isatin in the synthesis of organic compounds

“…115 This reaction has been widely studied and different catalysts such as [Amb]L-prolinate, 116 tetrabutylammonium bromide (TBAB), 117 boron nitride supported iron oxide (BN@Fe3O4), 118 AI-ITQ-HB, 119 [bmim]OH, 120 Fe3O4, 121 carbon nanotube (CNT), 122 NaOAc, 123 CuFe2O4 nanoparticles 124 and trisodium citrate dihydrate 125 were used in this reaction.…”

Cysteic acid grafted to magnetic graphene oxide as a promising recoverable solid acid catalyst for the synthesis of diverse 4H-chromene

“…Because of the benefits of MCRs and the great importance of 4 H -chromenes, syntheses of these compounds have been developed using different catalysts in the multicomponent reaction between malononitrile (or ethyl cyanoacetate), a diverse electron-rich phenol or enolizable carbonyl compound, and an aldehyde 1 . Recent catalytic systems for the synthesis of 4 H -chromene derivatives consist of Fe(HSO 4 ) 3 28 , nickel nanoparticles 29 , ZrO 2 nanoparticles 30 , Zn 4 O(H 2 N-TA) 3 31 , ZnS nanoparticles 32 , nano-sized MgO 33 , CoFe 2 O 4 34 , CuO-CeO 2 35 , egg shell 36 , chitosan 37 , polymer-supported palladacycles 38 , [2-aemim][PF 6 ] 39 and TMG-[bmim][X] 40 under microwave radiation, [bmim]OH 41 , IL-HSO 4 @SBA-15 42 , hexadecyltrimethylammonium bromide 43 , l -proline 44 , l -proline-melamine 45 , tetraalkylammonium halides 46 – 49 , SB-DBU.Cl 50 , potassiumphthalimide- N -oxyl 51 , potassium phthalimide 52 , sodium selenate 53 , sodium alginate 54 , Sodium ethylene diamine tetraacetate 55 , morpholine 56 , 4-dimethylamino- pyridine 57 , 4-DMAP 58 , piperidine 18 , 59 , piperidinium acetate 60 , (DHQD) 2 PYR 61 , tungstic acid functionalized mesoporous SBA-15 62 , 1,8-diazabicyclo[5.4.0]undec-7-ene 63 , glycine 64 , imidazole 65 , heteropolyacid 66 , meglumine 67 , Mg/Al hydrotalcite 68 , PEI@Si–MNP 69 , PEG-SO 3 H 70 , alumina 71 , nano-sized zeolite clinoptilolite 72 , Nickel Nanoparticles …”