Synthesis, X-ray and spectroscopic analysis of 2-chloro-4-(methoxymethyl)-6-methyl-5-nitropyridine-3-carbonitrile

Compound 2-chloro-4-(methoxymethyl)-6-methyl-5-nitropyridine-3-carbonitrile (2) has been obtained from 4-(methoxymethyl)-6-methyl-5-nitro-2-oxo-1,2-dihydropyridine-3-carbonitrile (1) by novel protocol using Vilsmeier-Haack chlorination and its solid state structure was analyzed using X-ray analysis. Structural features have been also studied by IR, NMR and electronic spectroscopy, and the optical properties were investigated by UV-vis absorption and fluorescence spectroscopy. Compound 2 crystallizes with two independent molecules in the asymmetric unit with almost identical geometric parameters. One C-H center dot center dot center dot O hydrogen bond self-assembles one type of independent molecule into chains, while second type is linked by one weak aromatic pi center dot center dot center dot pi stacking interaction. The absorption and fluorescence maximum of compound 2 were observed at 290 nm and 480 nm, respectively. The effects of solvents were investigated and interpreted on the emission spectra in protic and aprotic solvents in the range 200-600 nm. (C) 2010 Elsevier B.V. All rights reserved.