Solid state structure of new 5-[2-(N,N-diethylamino)ethoxy]-4,7-dimethylcoumarins by X-ray and 13C CP/MAS NMR

•We report microwave-assisted synthesis of new hydroxycoumarin derivatives.•The structures of new compounds were studied with X-ray diffraction technique.•The solid state structure was analyzed using the fully resolved 13C CP/MAS.

5-[2-(N,N-diethylamino)ethoxy]-4,7-dimethylcoumarin (1) and 6-acetyl-5-[2-(N,N-diethylamino)ethoxy]-4,7-dimethylcoumarin (2) were synthesized in a traditional way and microwave-assisted synthesis. Crystals of 2 in form of hydrochloride salt (3) were investigated using single crystal X-ray diffraction technique. In the crystal lattice of 3 there is only one type of strong hydrogen bond present involving protonated amino group and chloride anion. The whole structure is dominated by weak C–H…Cl−, C–H…O contacts. There is also visible aggregation of cations in stacks due to π–π interactions. The solid state structures of 1 and 2 derived from 13C CP/MAS NMR spectra were also proposed.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide