Polarized molecular-electronic structures and supramolecular aggregation in 1-(6-amino-1,3-benzodioxol-5-yl)-3-arylprop-2-en-1-ones

Molecules of 1-(6-amino-1,3-benzodioxol-5-yl)-3-(4-methylphenyl) prop-2-en-1-one, C17H15NO3, ( I), 1-(6-amino-1,3-benzodioxol- 5-yl)-3-(4-methoxyphenyl) prop-2-en-1-one, C17H15NO4, (II), and 1-(6-amino-1,3-benzodioxol-5-yl)-3-[4-( trifluoromethyl) phenyl] prop-2-en-1-one, C17H12F3NO3, (III), all contain an intramolecular N - H...O hydrogen bond and all exhibit polarized molecular - electronic structures. The molecules of ( I) are linked into simple sheets, generated by translation, by means of one N - H...O and one C-H ...(arene) hydrogen bond. Compound ( II) crystallizes as two concomitant polymorphs, viz. (IIa), with Z' = 1 in P2(1)/c, and (IIb), with Z' = 2 in P (1) over bar. In (IIa), intra- and intermolecular N - H...O hydrogen bonds generate a helical chain of rings, and these chains are linked into sheets by simple helical chains built from a C - H ...pi(arene) hydrogen bond, while in (IIb), the molecules are linked into simple chains by a C - H ... O hydrogen bond. In (III), where Z' = 2, each type of molecule forms a simple N - H ... O hydrogen-bonded chain generated by translation and the two types of chain are linked by a single pi-pi stacking interaction.