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The photoreduction of polybrominated diphenyl ethers (PBDEs)—a kind of persistent organic pollutants with high hydrophobicity—was achieved on graphene in aqueous solution. We first observed that reduced graphene oxide (RGO) exhibited higher reaction rate than graphene oxide (GO). FT-IR and elementary analysis indicated that GO first was reduced to RGO at the beginning of the irradiation, and RGO is the real photoactive species. The theoretical calculations and adsorption experiments reveal a new photochemical debromination pathway based on the weak interaction, such as hydrophobic interaction, π–π interaction, and halogen-binding interaction between the PBDEs and RGO. These interactions enable the photoinduced electron transfer from the RGO to PBDEs and lead to the efficient reductive debromination of PBDEs. This study provides a green and low-cost method for removal of the high hydrophobicity halogen organic pollutants in water with environmentally benign carbon nanomaterials.

As typical persistent organic pollutants, polybrominated diphenyl ethers (PBDEs) have aroused high environmental concern because of their toxicity and recalcitrant degradation. Here we report the visible-light-induced degradation of PBDEs with AgI–TiO2 (>420 nm). A series of nano-structured AgI–TiO2 particles were synthesized by a deposition–precipitation method and characterized by SEM, TEM, XRD, XPS, BET and UV-Vis-DRS. The AgI–TiO2 hybrids showed high efficiency for degradation of PBDEs and excellent photostability in cyclic run experiments. The absorbance intensity and absorption ability of AgI–TiO2 hybrids and the properties of the solvents were found to greatly influence the efficiency of degradation of PBDEs. The 0.2-AgI–TiO2 (the mass ratio of Ag to P25 was about 20%) in CH3OH solution presented the highest reaction rate with 0.29 ± 0.02 h−1. Most interestingly, mechanistic pathways in the degradation of PBDEs were different under UV and visible light. Unlike the common single-electron transfer in the UV-TiO2 system, the debromination mechanism in the visible light/AgI–TiO2 system showed multi-electron transfer. The analysis of products showed that many different lower brominated congeners simultaneously appeared under visible light rather than being stepwise formed under UV. This implies that the special structure of AgI–TiO2 performs remarkably enhanced electron transfer, multi-electron transfer, and results in high photocatalytic activity. This research may provide a green and efficient method to remove halogenated pollutants by using visible light.

An efficient, clean and facile protocol for the Knoevenagel condensation of aromatic aldehydes with active methylene compounds catalysed by task specific ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium acetate in an aqueous medium has been developed. The reactions proceed at room temperature and high to excellent yields were afforded. The workup procedure is very simple. The ionic liquid could be recycled for 10 runs without noticeably loss of its catalytic activity.

The DBU (1,8-Diazabicyclo[5.4.0]undec-7-ene) derived task-specific ionic liquids [DBU][Lac] (1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium lactate), [DBU][Ac] (1,8-diazabicyclo[5.4.0]-undec7-en-8-ium acetate) and [DBU][Tfa] (1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium trifluoroacetate) were synthesized. Among the three novel ionic liquids, [DBU][Lac] was found to have the highest catalytic activity for aza-Michael addition of aromatic amines to α,β-unsaturated ketones. The protocol can give good to excellent products yields and has advantages such as readily work-up and good reusability, which makes this method quite attractive.

A task-specific ionic liquid, 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium acetate has been successfully used as a catalyst for aza-conjugate addition of aliphatic or aromatic amines to various electron deficient alkenes under solvent-free conditions and at room temperature. The catalyst can be reused for six times without noticeable loss of activity.

Solid acid catalysts of SO 4 2− /TiO2/MCM-41 and S2O 8 2− /TiO2/MCM-41 were prepared via grafting method and sulfate/persulfate promotion. The catalysts exhibited desirable activity and better selectivity for cyclization reaction of pseudoionone compared to traditional SO 4 2− /TiO2. A combination of XRD, N2 adsorption–desorption and FTIR spectroscopy indicated that the catalysts possess well-ordered mesostructure, and the grafted TiO2 are in highly dispersed amorphous form rather than crystalline phase. For S2O 8 2− /TiO2/MCM-41 higher S content and more Bronsted acid sites can be achieved by persulfation, which is favorable for the protons participated cyclization reaction. The similar Si–O–Ti–O–S=O structure of all acid sites on pore surface of the catalysts is attributed to the improvement of selectivity in comparison with SO 4 2− /TiO2.

Several 6-aminoquinoline derivatives, which could be used in drug design, have been synthesized. The reaction conditions were comparatively studied, and the p -chloroaniline was used as optimum oxidant in Skraup–Doebner–Von Miller reaction. The nitro group was reduced effectively by SnCl 2 with no halo-removed occurred.

The title compound (common name eplerenone), C24H30O6, is an aldosterone receptor antagonist. From the isopropyl acetate solution the compound crystallizes in monoclinic space group P 21 with a = 8.811(1) A, b = 11.250(1) A, c = 11.079(1) A, β = 93.822(12)°, Z = 2. The molecule contains three six membered rings, two five membered rings and one three membered ring. Both five membered rings display envelope conformation, whereas three six membered rings show different conformation: chair, half-chair and envelope. In the crystal the eplerenone molecules link to one another via intermolecular weak C–H···O hydrogen bonding to form the smaller cavity of 12.0(1) A3 between eplerenone molecules, no solvent molecule filled in this cavity. In the title molecule three six-membered rings show different conformation. Weak C–H···O hydrogen bonding links adjacent molecules to form the small cavity 12.0(1) A3, no solvent molecule filled in the cavity.

The eplerenone mol­ecule of the title compound, C24H30O6·C4H8O, contains three six-membered rings, two five-membered rings and one three-membered ring. In the crystal structure, the eplerenone mol­ecules are linked via C—H⋯O hydrogen bonds, forming a 303 A3 cavity, which is occupied by two disordered solvent THF mol­ecules.

6-Aminoquinolines are available as potential intermediates in drug design using p-chloroaniline as an optimal oxidant in the Skraup—Doebner—von Miller reaction.

A task-specific ionic liquid, 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium acetate has been successfully used as a catalyst for aza-conjugate addition of aliphatic or aromatic amines to various electron deficient alkenes under solvent-free conditions and at room temperature. The catalyst can be reused for six times without noticeable loss of activity.

Eplerenone [systematic name: 7α-(methoxycarbonyl)-3-oxo-9α,11-epoxy-17α-pregn-4-ene-21,17-carbolactone], an aldosterone receptor antagonist, crystallizes from ethanol as a monosolvate, C24H30O6·C2H6O. The eplerenone molecule has two five-membered rings, three six-membered rings and one three-membered ring. Both five-membered rings display envelope conformations, while the three six-membered rings assume envelope (cyclohexene), half-chair (cyclohexane sharing one edge with epoxy) and chair (other cyclohexane) conformations. The solvent molecule is disordered equally over two sites. It is linked to the eplerenone molecule by hydrogen bonds.