Jian-Feng Zhou

A FACILE ONE POT SYNTHESIS OF PYRANO[2,3-c]PYRAZOLE DERIVATIVES UNDER MICROWAVE IRRADIATION

ABSTRACT A series of substituted pyrano[2,3-c]pyrazole derivatives were synthesized by the one pot reaction of aromatic aldehydes, malononitrile and 3-methyl-1-phenyl-2-pyrazolin-5-one under microwave irradiation in good yields.

One‐Step Synthesis of 2‐Aryl‐4,5‐diphenylimidazoles Under Microwave Irradiation

Abstract A series of 2‐aryl‐4,5‐diphenylimidazoles were synthesized by a one‐step condensation reaction of benzil, aromatic aldehyde, and ammonium acetate in acetic acid under microwave irradiation. The reactions were completed in 4–11 min with good yields and easy workup.

Catalyst-Free Synthesis of α,α-bis(4-Hydroxycoumarin-3-yl)toluene in Aqueous Media Under Microwave Irradiation

Abstract An efficient catalyst-free synthesis of α,α-bis(4-hydroxycoumarin-3-yl)toluene was performed by the reaction of 4-hydroxycoumarin with aromatic aldehydes in aqueous media under microwave irradiation. The reaction was completed in short reaction time of 8–10 min with high yields of 76–94, was environmental benign, and had easy workup. Their structures were confirmed by IR spectra, 1H NMR, 13C NMR, and elemental analysis.

Facile Synthesis of 5‐Benzylidene Rhodamine Derivatives under Microwave Irradiation

Abstract A series of 5‐benzylidenerhodamine derivatives were synthesized by the cross‐aldol condensation of an aromatic aldehyde with rhodamine or rhodamine acetic acid in sodium acetate/acetic acid under microwave irradiation. The reaction was completed in 8–20 min with 63–94% yields and was environmentally benign with easy workup.

Facile One-Pot, Multicomponent Synthesis of Pyridines Under Microwave Irradiation

Abstract A series of 2-amino-6-(2-oxo-2H-chromen-3-yl)-4-pyridine-3-carbo-nitriles were synthesized by the one-pot, multicomponent reaction of 3-acetyl-coumarin, aromatic aldehydes, malononitrile, and ammonium acetate in acetic acid under microwave irradiation. The reactions were completed in 10–13 min with 61–86% yields, were environmental benign, and had easy workup. Their structures were confirmed by 1H NMR, IR, and MS spectra and elemental analysis.

Microwave-Assisted Catalyst-Free and Solvent-Free Method for the Synthesis of Quinoxalines

Abstract A green and efficient procedure for the synthesis of quinoxalines is reported starting from benzil and 1,2-diaminobenzene. The reactions were carried out under catalyst-free, solvent-free, and microwave-irradiation conditions, affording the corresponding quinoxalines. This method had many dramatic advantages, such as the short reaction time (2–6 min), high yields (71–98%), and environmental friendliness, as well as convenient operation.

Chemical composition, antioxidant and antimicrobial activity of the extracts of the flowers of the Chinese plant Chimonanthus praecox

This study investigated the antimicrobial and antioxidant activity of the extracts of the flowers, essential oil (EO) and semi-volatile fractions (SVF) of Chimonanthus praecox. The chemical composition of the EO was analysed by gas chromatography-mass spectroscopy (GC–MS) which revealed that the EO contained elemene, muurolene, caryophyllene, cadinol and spathulenol. The effective antibacterial activity of the EO suggested that its different responses on the microorganisms studied depended on the synergistic effects of the compounds contained in the EO. The effective antioxidant activity of the EO showed that the EO had a more marked antioxidant effect on scavenging · and OH· than DPPH·, and SVF had a higher potential for scavenging DPPH· than the EO. Our data suggested that the flowers of Chimonanthus praecox had pharmaceutical benefits, and are also a potential source of natural antioxidants and biocides.

Facile Method for One-Step Synthesis of 2,4,5-Triarylimidazoles Under Catalyst-Free, Solvent-Free, and Microwave-Irradiation Conditions

A green and efficient method for the synthesis of 2,4,5-triarylimidazoles by one-step condensation reaction of benzil, aromatic aldehyde, and ammonium acetate under catalyst-free, solvent-free, and microwave-irradiation conditions is reported. This method had many dramatic advantages, such as the short reaction time (3–5 min), good yields (80–99%), environmental friendliness, and convenient operation.

Efficient One-Pot Synthesis of Tetrahydrobenzo[c]xanthene-1,11-dione Derivatives Under Microwave Irradiation

Abstract An efficient one-pot condensation of 4-hydroxylcoumarin, aromatic aldehydes, and 5,5-dimethylcyclohexane-1,3-dione has been achieved with molecular iodine as a catalyst via conventional heating and microwave irradiation techniques, and thus a variety of new tetrahydrobenzo[c]xanthene-1,11-dione derivatives were prepared in good yields. GRAPHICAL ABSTRACT

A Facile Synthesis of 5-Arylidene-2-imino-4-thiazolidinones Under Microwave Irradiation

Abstract A series of 5-arylidene-2-imino-4-thiazolidinone derivatives were synthesized by the cross-aldol condensation of aromatic aldehydes with 2-imino-4-thiazolidinone in sodium acetate/acetic acid under microwave irradiation. The reactions were completed in 10 min with 63–91% yields, were environmental benign, and had easy workup.