(Difluoromethylene)cyclopropane

[67884-64-4] C4H4F2 (MW 90.07) InChI = 1S/C4H4F2/c5-4(6)3-1-2-3/h1-2H2 InChIKey = KISFZKFADXZJFK-UHFFFAOYSA-N (reagent used to react with various dienes through a [2 + 2] cycloaddition process to form a CF2-containing cyclobutane moiety) Physical Data: bp 6.5 ± 15 °C; the boiling point is not reported in the literature. This value was calculated using the Advanced Chemistry Development (ACD/Labs) Software Solaris V4.76 [© 1994-2004 ACD/Labs] Solubility: assumed to be soluble in common organic solvents such as CHCl3, THF, and acetone. Form Supplied in: colorless liquid under cooling conditions, or a gas at ambient temperature, not available commercially. Purification: GLPC (15 ft × 1/4 in. 20% SE-30 column at 25 °C), collect in a cold trap. Preparative Methods: is prepared in multigram quantities by the sealed tube thermal rearrangement of 2,2-difluoromethylenecyclopropane 2 at 260–300 °C under vacuum for 30–40 min (88% conversion yield)1, 2 (eq 1). (1) Handling, Storage, and Precaution: is a low boiling liquid under cooling conditions, and presumably is stable at low temperature. It is the best to store in a gas cylinder, and handle as a gaseous compound.