3-(1-Methylpyrrolidin-2-ylidene)-3H-indole sesquihydrate

Abstract

The asymmetric unit of the title compound, C13H14N2·1.5H2O, contains two similar molecules of 3-(1-methylpyrrolidin-2-ylidene)-3H-indole, (I), and three water molecules. (I) is the product of reacting indole with 1-methylpyrrolidin-2-one in the presence of phosphorus oxychloride. Both organic molecules are almost completely planar; the maximum distances above and below the least-squares plane through all the atoms of molecule 1 are 0.050 (8) and −0.045 (8) Å, respectively, and the deviations for molecule 2 are 0.096 (8) and −0.059 (8) Å, respectively. In the crystal, the two crystallographically different molecules alternate in π-stacked columns [centroid–centroid distances = 3.729 (5) and 3.858 (5) Å], which are linked by O—H...N hydrogen bonds to a network of hydrogen-bonded water molecules. O—H...O interactions are also present.