the ionic liquid li(ohch2ch2nh2)(cf3oac) was found to efficiently catalyze the three-component reaction between different enols, aldehydes, and malononitrile , leading to rapid synthesis of 2-amino-4h-chromene derivatives in fairly high yields. the catalyst is easily prepared, highly stable, simple to handle and recycled for several times without significant loss of activity. the method is simp...

sucrose is applied as an efficient catalyst for the three-component reaction consisting of aromatic aldehydes, malononitrile and resorcinol in a mixture of water and ethanol media as green solvents. the advantages of this method are excellent yeild, inexpensive catalyst and more environmentally friendly. mechanistic insight into the synthesis of 2-amino-4h-chromene included spectral kinetics ap...

3,4-ِdihydropyrano[c]chromene derivatives were synthesized using sulfonic acid functionalized silica (sio2-pr-so3h) as a highly efficient heterogenous solid acid catalyst via one-pot three-component condensation of aromatic aldehydes with malononitrile and 4-hydroxycoumarin in excellent yields.

An unexpected transformation of 2H-chromene-3-carboxaldehydes to coumarin derivatives, mediated by NHC, is reported.

Three coumarin derivatives, viz. 6-methyl-N-(3-methyl-phen-yl)-2-oxo-2H-chromene-3-carboxamide, C18H15NO3 (1), N-(3-meth-oxy-phen-yl)-6-methyl-2-oxo-2H-chromene-3-carboxamide, C18H15NO4 (2), and 6-meth-oxy-N-(3-meth-oxy-phen-yl)-2-oxo-2H-chromene-3-carboxamide, C18H15NO5 (3), were synthesized and structurally characterized. The mol-ecules display intra-molecular N-H⋯O and weak C-H⋯O hydrogen bo...

Chromene is considered a fused pyran ring with benzene ring, which found in many plants and part of important compounds such as anthocyanidins, anthocyanins, catechins, flavanones. These are included under the headings "flavonoids" "iso-flavonoids." well known bioactive molecules wide medicinal uses. According to these pharmacokinetic characteristics, researchers giving more attention this type...

A one-pot procedure was developed for the synthesis of novel 3-[amino(methoxy)methylene]-2-oxo-3,4-dihydro-2H-chromen-4-yl)-3-cyanoacetamides and chromeno[3,4-c]pyridine-1-carbonitriles from the reaction of 2-oxo-2H-chromene-3-carbonitriles and cyanoacetamides. These chromene derivatives were identified as new scaffolds for adenosine receptors and the hits 3a, 3c, 5a, and 5b were found.

The cesium carbonate-mediated reaction of 2-bromoallyl sulfones and ortho-hydroxychalcones furnished 3-arylsulfonyl-4H-chromene derivatives in 58-67% yield (18 examples). 2-Bromoallyl sulfones functioned as synthetic surrogates for allenyl sulfones in the reaction.

The reaction of dimethyl acetylenedicarboxylate with OH-acid such as 2-naphthol in the presence of trimethyl or triphenyl phosphite under solvent-free conditions produce oxaphosphaphenanthrene derivatives in good yields. Also, the reaction of dimethyl acetylenedicarboxylate and trimethyl phosphite in the presence of 1-naphthol leads to succinate derivatives in excellent yields. Using triethyl p...

Efficient kinetic resolution of racemic 3-nitro-2H-chromenes by bifunctional thiourea afforded optically active (R)-3-nitro-2H-chromene derivatives with moderate to good enantioselectivities, which simultaneously gave the multifunctional 3,4-diphenyl-3a-nitrobenzopyrano-[3,4-c]-pyrrolidine-1,1-dicarboxylate derivatives with four vicinal chiral carbon centers.