3,3-difluorocyclobutane-1-sulfonyl chloride

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of potassium 3,3-difluorocyclobutane-1-sulfonate (0.250 g, 1.189 mmol) in thionyl chloride (2.60 mL, 35.7 mmol) was added DMF (3 drops). The reaction was heated to about 60° C. for about 21 h. The solvent was removed under reduced pressure and the residue was used in the next reaction without further workup or purification to afford crude 3,3-difluorocyclobutane-1-sulfonyl chloride (0.227 g, 100%) as product. 1H NMR (400 MHz, CDCl3) δ 4.33-4.17 (m, 1H), 3.28 (dd, J=11.1, 7.6 Hz, 2H), 3.21-3.05 (m, 2H). The solvent was removed under reduced pressure the residue was used in the next reaction without further workup or purification