In(OTf)3 catalyzed microwave-assisted alkenylation of methoxyphenols was investigated. Exclusive formation of either indenes or chromenes was observed depending on the position of the methoxy group on phenol. The structures of 1H-inden-4-ol derivatives (4a-e) and 4H-chromene derivatives (5a-j) were established by NMR ((1)H & (13)C) and high-resolution mass spectra, which were further supported ...

The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields.

The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields

The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields.

silica-bonded n-propyltriethylene-tetramine (sbnptt) was found as an efficient solid base for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4h-chromenes. chromene derivatives were obtained via the three-component condensation reaction of aromatic aldehydes, malononitrile, and dimedone at 80 oc under solvent-free conditions. the heterogeneous solid base showed much the same efficiency when u...

The reactions of 2-perfluoroacyl-1H-benzo[f]chromenes and 6,7-dimethyl-3-trifluoroacetyl-4H-chromene with primary aliphatic amines ammonia afforded a series enamino ketones containing (2-hydroxynaphthalen-1-yl)methyl or 2-hydroxybenzyl substituent in the ?-position respect to carbonyl group. These involved opening pyran ring, which followed aza-Michael addition as initial step. obtained were fo...

Silica-bonded n-propyltriethylene-tetramine (SBNPTT) was found as an efficient solid base for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-chromenes. Chromene derivatives were obtained via the three-component condensation reaction of aromatic aldehydes, malononitrile, and dimedone at 80 oC under solvent-free conditions. The heterogeneous solid base showed much the same efficiency when u...

In this study, we reported facile and efficient synthesis of 2-amino-4H-chromenes that catalyzed by polystyrene-supported 1-methylimidazolium tetrachloroferrateas. The synthesis proceeds with various aldehydes under mild conditions and afford the target products with good to high yields.

in this research, so3h-functionalizedphthalimide (sfp) has been prepared through simple reaction of phthalimide with chlorosulfonic acid, and characterized using ft-ir, 1h nmr, 13c nmr, sem (scanning electron microscopy), mass and tg (thermal gravimetric) spectra. afterward, the solid acid has been utilized as an efficient, green, heterogeneous and recyclable catalyst for the solvent-free synth...