A 3 mm NMR tube was sealed with a septum, wrapped in parafilm, and dried with a heat-gun under vacuum. The tube was backfilled with Ar, then 0.1 mL of a standard solution was added to the tube. Then, 0.3 mL dry CDCl3 was added followed by a 0.2 mL aliquot of the SF5Cl solution. During data collection, the d1 relaxation delay was set to 20 s, with 8 scans and 0 dummy scans.