Solvent-Free Green and Efficient One-Pot Synthesis of Dihydropyrano[3,2-c]chromene Derivatives

Abstract

A rapid, clean, and highly efficient method for synthesis of dihydropyrano[3,2-c]chromene derivatives by one-pot, three-component condensation of aromatic aldehydes, malononitrile, and 4-hydroxycoumarin using DABCO as catalyst in solvent-free neat conditions is described. The present method has the advantages of mild reaction conditions, short reaction times, easy isolation of products, and excellent yields.

The versatility of DABCO as a reagent in organic synthesis: a review

“…The reaction has several advantages, including a high product yield, a fast reaction rate and gentle reaction conditions (Scheme 64). 121 Table 31 shows the variation of yield of dihydropyrano[3,2- c ] chromene derivatives catalyzed by DABCO with change in reaction conditions.…”

Design, preparation, and characterization of Fe3O4 nanoparticles encapsulating β‐cyclodextrin‐bearing guanidine as a highly efficient and reusable heterogeneous base catalyst for synthesis of 3,4‐dihydropyrano[3,2‐c]chromenes

“…Therefore, the development of efficient methods for the synthesis of these important heterocycles has attracted researchers' attention. Various methods have been reported for the synthesis of these compounds in the presence of a variety of catalysts, such as thiourea dioxide, [13] DABCO, [14] DBU (1,8-Diazabicyclo[5.4.0]undec-7-ene), [15] dehydroabietylamine-cinchonine-squaramide, [12] magnetic nanoparticles tag: piperidinium benzene-1,-3-disulfonate ionic liquid, [16] polypyrrole/Fe 3 O 4 /Carbon nanotube (CNT), [17] ammonium acetate, [18] Ni(II)functionalized Li + -montmorillonite, [19] sodium benzenesulfinates, [20] sodium malonate, [21] nano-SiO 2, [22] o-benzene disulfonimide, [23] potassium phthalimide, [24] crown ether complex cation ionic liquids, [25] and N,N-dimethylbenzylamine. [26] Cyclodextrins (CDs) are cyclic oligomers made up of α-(1,4)-linked D-glucopyranose units.…”

A Green and Efficient Method for the Synthesis of 3,4- Dihydropyrano[c]chromene using Phosphate Fertilizers (MAP, DAP and TSP) as Heterogeneous Catalysts

“…Other heterogeneous catalysts as hydroxyapatite (10)(11)(12)(13) and fluoroapatite (14)(15)(16) are also used in organic synthesis. In particular our work is aimed to 3,4dihydropyrano[c]chromene synthesis, which gains a lot of attention due to their various biological activities (17)(18)(19)(20)(21)(22), they are well known as spasmolytic, diuretic, anticoagulant, anti-cancer and anti-anaphylactic, they can also be used as cognitive enhancers, for the treatment of neurodegenerative diseases, including Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, Parkinson's disease, AIDS-associated dementia and Down syndrome as well as for the treatment of schizophrenia and myoclonus (23) .…”