A green and convenient method for the synthesis of 14-aryl-14H-dibenzo[a,i]xanthene-8,13-diones and spiro[dibenzo[a,i]-xanthene-14,3'-indoline]-2',8,13-triones in the presence of a catalytic amount of cellulose sulfuric acid (CSA) as an efficient biopolymer-based catalyst under solvent-free conditions at 100 °C is described. The condensation reactions of β-naphtol, 2-hydroxynaphthalene-1,4-dion...

Fluorescence emission after two-photon absorption of coumarins and xanthenes in an alcoholic solution was measured in the tuning range of a femtosecond-pulsed titanium-sapphire laser (750-840 nm). Xanthenes, which have a low one-photon absorption in the near UV, show a higher fluorescence signal after two-photon absorption than the UV-excitable coumarins. When fluxes of 10(28) photons/(cm(2) s)...

poly(4-vinylpyridine)-supported copper iodide nanoparticles is reported as a new, green and recyclable catalyst for the synthesis of aryl-14h-dibenzo [a-o] xanthenes under solvent-free conditions. this catalyst can be recovered by simple filtration and recycled up to 8 consecutive runs without any loss of their efficiency.

A convenient, efficient and practical procedure for the synthesis of 1-amidoalkyl 2-naphthols is described by condensation of aromatic aldehydes with amides and 2-naphthol in the presence of P2O5/SiO2 as an efficient catalyst. Moreover, in the present of this catalyst, the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes is studied by co...

A large number of analytical methods for the detection of chlorinated dibenzo-p-dio-xins have been reported in the past few years (1-8) ; generally, these methods involve the use of gas-liquid chromatography (GLC) or GLC coupled with mass spectrometry (MS). Detection limits of about 1 ng have been reported for GLC-MS techniques with the demonstrated capability of detecting these compounds in th...

a simple and environmentally benign procedure for the synthesis of 14-aryl-14h-dibenzo[a,j]xanthenes by a one-pot condensation of 2-naphthol with aromatic aldehyde in the presence of [et3nh][hso4] as an acidic ionic liquid catalyst under solvent-free conditions has been developed. the reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused s...

14-aryl- and 14-alkyl-14-h-dibenzo [a,j]xanthenes are prepared from the reaction of aromatic- and aliphaticaldehydes with β-naphthol in the presence of catalytic amounts of 4-dodecylbenzenesulfonic acid(dbsa) as asurfactant-type brønsted acid catalyst in toluene and under solvent-free conditions in excellent yields and shortreaction times. the catalyst was recovered and reused for five successi...

Phthalimide was reacted with chlorosulfonic acid to give sulfonic acid-functionalized phthalimide (SFP), which characterized by 1H NMR, 13C NMR, FT-IR, XRD (X-ray diffraction), SEM (scanning electron microscopy), EDX (energy-dispersive X-ray), mass, TG (thermogravimetry) and DTG (derivative thermal gravimetry) spectra. Afterward, its catalytic activity was examined for the condensation of aryla...

Phthalimide was reacted with chlorosulfonic acid to give sulfonic acid-functionalized phthalimide (SFP), which characterized by 1H NMR, 13C NMR, FT-IR, XRD (X-ray diffraction), SEM (scanning electron microscopy), EDX (energy-dispersive X-ray), mass, TG (thermogravimetry) and DTG (derivative thermal gravimetry) spectra. Afterward, its catalytic activity was examined for the condensation of aryla...

A convenient, efficient and practical procedure for the synthesis of 1-amidoalkyl 2-naphthols is described by condensation of aromatic aldehydes with amides and 2-naphthol in the presence of P2O5/SiO2 as an efficient catalyst. Moreover, in the present of this catalyst, the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes is studied by co...