Toluene → Poly(difluoromethylene), alpha-(2-((2-carboxyethyl)thio)ethyl)-omega-fluoro-

Participants

Reaction Steps

A 250 mL three-neck round bottomed flask was charged with toluene (81 mL) and cooled to <−50° C. with a dry ice/acetone bath. 3,3,3-Trifluoropropene (10.28 g, 107.0 mmol) was bubbled into the solvent and the ice bath was removed. 3-Mercaptopropionic acid (9.200 g, 86.70 mmol) and 2,2-dimethoxy-2-phenylacetophenone (1.070 g, 4.170 mmol) was added and the long wave light (366 nm, 4 watt UVP lamp) was turned on (Starting temperature: −24° C.). The reaction reached a high temperature of 27.5° C. due to heat from the lamp. The reaction was stirred with the black light on for 4 hours. After 4 hours the black light was turned off and the reaction concentrated by rotary evaporation (41° C., 6 mm Hg) giving a pale yellow oil (18.09 g, 51:1 linear:branched isomer, 90 wt % linear isomer by GC internal standard assay, 16.26 g active, 93%). The crude material was dissolved in 10% sodium hydroxide w/w (37.35 g) and was washed with toluene (30 mL) to remove non-polar impurities. The aqueous layer was acidified to pH˜2-3 with hydrochloric acid (2 N, 47.81 g) and was extracted with toluene (50 mL). The organic layer was washed with water (40 mL) and dried over magnesium sulfate, filtered, and concentrated by rotary evaporation giving a pale yellow oil (14.15 g, 34:1 linear:branched isomer, 94 wt % linear isomer by GC internal standard assay, 13.26 g active, 76%).

Provenance & Evidence