Single crystal X-ray diffraction data were collected at 160.0(1) K on a Rigaku OD Synergy/Hypix diffractometer using the copper X-ray radiation (λ = 1.54184 Å) from a dual-wavelength X-ray source and an Oxford Instruments Cryojet XL cooler. The selected suitable single crystal was mounted using polybutene oil on a flexible loop fixed on a goniometer head and immediately transferred to the diffractometer. Pre-experiment, data collection, data reduction and analytical absorption correction were performed with the program suite CrysAlisPro. Using Olex2, the structure was solved with the SHELXT small molecule structure solution program and refined with the SHELXL program package by full-matrix least-squares minimisation on F 2 . PLATON was used to check the result of the X-ray analysis.