| Summary: | 3-(2-Chlorobenzylidene)-5-(<i>p</i>-tolyl)furan-2(3<i>H</i>)-one (<b>1</b>), C<sub>18</sub>H<sub>13</sub>ClO<sub>2</sub>, crystallizes with <i>Z</i> = 8 and <i>Z′</i> = 2, and the structure at 100 K has orthorhombic (<i>Pna</i>2<sub>1</sub>) symmetry. Each kind of molecule takes part in π–π stacking interactions to form infinite chains parallel to the <i>c</i> axis. We believe that the existence of two forms can be explained by the probable rotation around a single C–C bond. The quantum chemical modeling reveals that these molecules are almost equivalent energetically, and they can be described as the two most stable conformers (rotamers) with a minor rotational barrier of about 0.67 kcal/mol.
|
|---|
