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A facile and efficient one-pot synthesis of 3-(furan-2-yl)-4-hydroxy-2H-chromen-2-ones was developed. The reaction of ethyl 3-(2-hydroxyphenyl)-3-oxopropanoates and 2,5-dimethoxy-2,5-dihydrofuran were performed in presence of K10 Montmorillonite Clay heterogeneous catalyst under the solvent-free condition at 80 °C for 1 h, and followed by further converted to 3-(furan-2-yl)-4-hydroxy-2H-chromen-2-ones via refluxing in the alkaline EtOH solution for 0.5 h. The demonstrate method not only avoided the usage of any expensive transition-metals, but also eliminated the tedious intermediate purification. Moreover, due to the wide functional group tolerance, it could be applied to various substrates and gave product in good to excellent yields.

A series of 3,4-diaryl- 1H -pyrazoles derivatives were designed and synthesized by the reaction of 3-heteroarylchromones and 3-phenylchromones with hydrazine hydrate in good yields. All of those compounds were characterized by 1 H NMR, 13 C NMR, IR, and HRMS. Moreover, 3-(2,4-dihydroxyphenyl)-4-(4-hydroxyphenyl)- 1H -pyrazole and 3-(2,4-dihydroxy phenyl)-4-(4-methoxyphenyl)- 1H -pyrazole were further conformed by the single crystal X-ray diffraction. In addition, the antifungal activity against five phytopathogenic fungi ( Cytospora sp., Colletotrichum gloeosporioides , Botrytis cinerea , Alternaria solani and Fusarium solani ) of 3,4-diaryl- 1H -pyrazoles were evaluated. 3-(2-Hydroxy-4-isopropoxyphenyl)-4-phenyl- 1H -pyrazole was more better and broader inhibitory effect on Cytospora sp., C. gloeosporioides , A. solani and Fusarium solani with IC 50 values of 26.96, 28.84, 16.77 and 22.10 μg/mL, respectively. 4-(4-Fluorophenyl)-3-(2-hydroxy-4-methoxyphenyl)- 1H -pyrazole exhibited fairly effective antifungal activity against Cytospora sp., C. gloeosporioides and A. solani with IC 50 values of 11.91, 14.92 and 16.98 μg/mL, respectively.

Presented here is a new porous tetrahedral Zn(II)-tetrazolate framework, namely [Zn2(mtz)3(OH)]n·n(DMF) (1, Hmtz = 5-methyl-1H-tetrazole, DMF = N,N’-dimethylformamide), has been successfully synthesized under solvothermal conditions. Single crystal X-ray structural analysis reveals that compound 1 features a three-dimensional (3D) porous framework with 4-connected dia-type topology. The 1D channels along the crystallograhical c axis are occupied by the lattice DMF molecules. The desolvated samples show highly adsorption selectivity of CO2 over N2.

An efficient, oxidant and photocatalyst-free approach for the synthesis of polycyclic-fused isoindolinone derivatives is reported via annulation of 3,4-diphenyl-3-pyrrolin-2-ones along with release of the hydrogen gas under an argon atmosphere in EtOH by irradiation with a 500 W mercury lamp at room temperature. The described approach is atom-economic and environmentally friendly and tolerates various electron-donating and electron-withdrawing groups. In addition, selected annulation products, dibenzo[e,g]isoindole-1-ones, were successfully oxidized into dibenzo[e,g]isoindole-1,3(2H)- diones in DMSO in the presence of CH3ONa at room temperature.

New vertically π-expanded coumarins dyes 1-phenynyl-2H-phenaleno[1,2,3-de] chromen-2-ones and 1-cyano-2H-phenaleno[1,2,3-de]chromen-2-ones were synthesized using 1-bromo-2H-phenaleno[1,2,3-de]chromen-2-one with arylacetylene or cyano reagent via the Sonogashira reaction and cyanide substitution reaction, and obtained in high yields up to 85% from 1-bromo-2H-phenaleno [1,2,3-de]chromen-2-one. The photophysical studies revealed that 1-substituted -2H-phenaleno[1,2,3-de]chromen-2-ones have large Stokes shift (4898 cm−1) and excellent fluorescence quantum yield (Φf = 0.80) along with significant bathochromic shift. The intriguing optical properties of these vertically π-expanded coumarins are discussed on the basis of quantum chemical calculations. Furthermore, 1-cyano-2H-phenaleno[1,2,3-de]chromen-2-one exhibited good biocompatibility by onion skin staining.

Under microwave radiation, isomers 2-(pyrazolo[1,5- a ]pyrimidin-5-yl)phenols ( 3 ) and 2-(pyrazolo[1,5- a ]pyrimidin-7-yl)phenols ( 4 ) were simultaneously obtained by the condensation of chromones and 3-aminopyrazoles. These two isomers were fully characterized by IR, 1 H NMR, 13 C NMR and HRMS. In addition, a representative product 5-chloro-2-(2-methyl-pyrazolo[1,5- a ] pyrimidin-5-yl)phenol ( 3e ) was further conformed by the single crystal X-ray diffraction. The antifungal abilities of the obtained products 3 and 4 were evaluated against five phytopathogenic fungi ( Cytospora sp., Colletotrichum gloeosporioides , Botrytis cinerea , Alternaria solani and Fusarium solani ). The results revealed that 2-(pyrazolo[1,5- a ]pyrimidin-5-yl)phenol ( 3a ) and 4-chloro-2-(2-methylpyrazolo[1,5- a ]pyrimidin-7-yl)phenol ( 4e ) exhibited good antifungal abilities against Colletotrichum gloeosporioides with the IC 50 values of 24.90 and 28.28 μ g/mL, respectively.

Benzo[h]-naphth[1,2-f]quinazolines and benzo[h]-phenanthren[9,10-f]quinazoines were synthesized from intermediates 4-(2-hydroxyphenyl)-5-(naphthalen-1-yl)pyrimidines and 4-(2-hydroxyphenyl)-5-(phenanthren-1-yl) pyrimidines by the intramolecular dehydration of photocyclization. The intermediates were obtained by the condensation of 3-arylchromone with formamidine, acetamidine or guanidine refluxing in ethanol, respectively. Irradiation of the corresponding intermediates by a high-pressure mercury lamp in 19:1 (v/v) EtOH H2O or 18:1:1 (v/v) EtOH H2O-Dioxane lead to target products. This photocyclization showed advantages including catalyst-free and mild reaction condition. Moreover, water was the only by-product of this reaction. The crystal structure of 2-amino-12-methoxy-benzo[h]-naphth[1,2-f]quinazoline was determined and the fluorescence properties of these polybenzoquinazolines were also investigated.

Four water-soluble sodium 8-carboxy-7-hydroxy-6-oxo-6H-benzo[c]chromene-2-sulfonates (2a-2d) were prepared and structurally characterized by 1H NMR, 13C NMR and HRMS-ESI spectra. The experimental results showed that 2a-2d were new water-soluble photoluminescent materials with strong photoluminescence property, large quantum yield and Stokes shift. In view of the high fluorescence quantum efficiency, 8-carboxy-7-hydroxy-3-methoxy-6-oxo-6H-benzo[c]chromene-2-sulfonate (2b, Ф = 0.74) was applied to the detection of Fe3+ in water solution. And probe 2b not only exhibited a naked-eye color change from colorless to pink, but also displayed highly selective ‘‘turn-off’’ probe for Fe3+ with detection limit of 1.72 umol/L in comparison to Na+, K+, Ag+, Ca2+, Cd2+, Co2+, Cu2+, Mg2+, Ni2+, Pb2+, Zn2+, Al3+ and Cr3+ cations in Tris-HCl buffer solution (pH 7.24). Futhermore, the binding stoichiometry of 2b with Fe3+ was determined to be 1:1 by Job’s plot. Because of the good water-solubility and strong fluorescence in physiological pH, 2b was applied in monitoring intracellular Fe3+ of living Ramos cells successfully.

Four metal–organic coordination polymers, CsL1(H2O)3 (1), CsL2·H2O (2), [CsL3(H2O)2]·H2O (3) and [RbL3(H2O)2]·H2O (4) were successfully synthesized by the self-assembly of Cs(I), Rb(I) and ligands L1–L3[L1 = 7-ethoxy-4′-methoxyisoflavone-3′-sulfonate, L2 = 6-fluoro-4′-methoxyisoflavone-3′-sulfonate, L3 = 5,7-dihydroxy-6,4′-dimethoxyisoflavone-3′-sulfonate]. Single crystal X-ray diffraction analyses show that 1–4 have an intriguing variety of structural features with the change of isoflavone-3′-sulfonates. A variety of non-covalent interactions such as coordination interaction, aromatic stacking and hydrogen bonding exist in their crystal structures, which together with the electrostatic interaction between the Cs+, Rb+ and the sulfonate anions assemble 1–4 into three-dimensional supramolecular structures. Sulfo-groups of L1–L3 play important roles, they not only can coordinate with Cs+ or Rb+ directly, but also provide important bridges in structural link between the organic and the inorganic region in 1–4.

Sodium 8-bromo-5,7-dihydroxyl-4′,6-dimethoxylisoflavone-3′-sulfonate (NaX, X = C17H12O6BrSO3−) was synthesized with irisolidone as a leading compound, which was characterized by elemental analysis, 1H NMR and IR spectra. The self-assembly of X with metal(II) (M = Co, Zn, Fe, Ni, Mg, Cd) lead to the formation of six compounds, [M(H2O)6(X)2]·H2O (1–6). Single-crystal X-ray diffraction results of 1–6 revealed that they were isomorphous and the introduction of Br atom and –SO3− group to 5,7-dihydroxyl-4′,6-dimethoxylisoflavone facilitated the collaboration of electrostatic interaction, hydrogen bonding, π⋯π stacking interaction and the rare Br⋯π interaction, leading to three-dimensional supramolecular architectures.