The initial search found 153 structures containing the predefined entity. Complete .cif-data of the compound are available under the CCDC number CCDC-2195538. The investigated crystal is twinned by inversion (TWIN -1 0 0 0 -1 0 0 0 -1) with a free refined BASF value of 0.5 (3). Additionally, the molecule is located on a crystallographic special position (two fold rotational axis) and the bicyclo [1.1.1]pentane unit is rotationally disorderd over two positions. This group was refined with fixed occupancy of 50% for PART -1.