Direct Syntheses of Diphenylmethanol Derivatives from Substituted Benzenes and CHCl3 through Friedel-Crafts Alkylation and Post-Synthetic Hydrolysis or Alcoholysis Catalyzed by Alumina.

The present study reports an innovative finding that alumina containing water or primary alcohol catalyzes the hydrolysis or alcoholysis, respectively, of the product formed through AlCl3 -mediated Friedel-Crafts alkylation of methyl-substituted benzenes and CHCl3 . The former and later reactions mainly provided hydroxy- and alkoxy-substituted diarylmethanes, respectively, while the reference reactions without alumina provided bisarylchloromethane. This method enables the selective syntheses of diphenylmethanol derivatives with very simple procedures, without expensive reagents and apparatuses. Furthermore, the alumina used in the reaction could be recycled by washing with water and subsequent drying. From the viewpoint of material recycling, this function is very important for the development of sustainable chemical reactions.

Hydroxychalcone dyes that serve as color indicators for pH and fluoride ions.

A chalcone, which is composed of two aromatic rings bridged by an α,ß-unsaturated carbonyl group, exhibits a variety of biological activities. With an objective to develop a novel chalcone-based functional dye, we have synthesized a chalcone diol CLN1, bearing two OH groups at the 2-positions on both phenyl rings, as well as reference compounds CLN2-6, and found that it serves as color indicators for pH and fluoride ions. CLN1 showed a vivid color change from colorless to yellow (halochromism) in water at pH ≥ 10. Furthermore, it presented a selective color change from colorless to red upon the addition of TBAF in an organic solvent such as CH3CN. CLN1 provided a strong red-shifted absorption band in the visible region under alkaline conditions in water and upon the addition of TBAF in CH3CN. The absorption spectral study together with TD-DFT calculations and X-ray crystallographic analysis revealed that the characteristic π-resonant structures of CLN1 caused by the ionization or OH-F- interactions and the planar conformation due to its intramolecular hydrogen bonding may provide a strong charge transfer (CT) absorption in the visible region.

A series of Mn(i) photo-activated carbon monoxide-releasing molecules with benzimidazole coligands: synthesis, structural characterization, CO releasing properties and biological activity evaluation.

Five Mn(i) photo-activated carbon monoxide-releasing molecules (photo-CORMs) with benzimidazole coligands, namely [MnBr(CO)3L1] (1, L1 = 2-(2-pyridyl)benzimidazole), [Mn(CO)2L1(PPh3)2](ClO4) (2), [MnBr(CO)3L2] (3, L2 = 2,2'-bisbenzimidazole), [MnBr(CO)3L3]·CH3OH (4, L3 = 2,6-bis(benzimidazole-2'-yl)pyridine) and fac-[MnBr(CO)3L4] (5, L4 = 2,4-bis(benzimidazole-2'-yl) pyridine) were synthesized by reactions of MnBr(CO)5 with complexes L1-L4, respectively, and characterized via single crystal X-ray diffraction, elemental analysis, 1H-NMR, 13C-NMR, IR, UV-vis and fluorescence spectroscopy. The CO-release properties of 1-5 were investigated using the myoglobin assay and CO detection, and the results show that all of the complexes could release CO rapidly upon exposure to 365 nm UV light. Comparing their half-lives of CO release, we found that increasing the degree of unsaturation and conjugation of the ligand frame could be advantageous for prolonging the time of CO-release, and that the luminescence intensity of 1-5 could gradually be enhanced. The cellular fluorescence imaging tests demonstrate that these Mn(i) photo-CORMs can be taken up by human liver cells (HL-7702) and liver cancer cells (SK-Hep1), and exhibit good capabilities for bioimaging. A cell viability assay for SK-Hep1 shows that the anticancer activity of 3 is better than that of other complexes.