X-ray crystallographic analysis of sulfoxide derivatives: A) 1,1,1-trifluoro-3-(butane-1-sulfinyl)propane-2,2-diol, compound 6; B) 1,1,1-trifluoro-3-(hexane-1-sulfinyl)propane-2,2-diol, compound 7; C) 1,1,1-trifluoro-3-(octane-1-sulfinyl)propane-2,2-diol, compound 8; D) 1,1,1-trifluoro-3-(decane-1-sulfinyl)propane-2,2-diol, compound 9. Intermolecular hydrogen bonds are shown as dashed lines. No intramolecular hydrogen bonds were observed.