nmr 151 mhz cdcl 3 u03b4 157 27 t j 6 0 hz 131 94 t j 1 9 hz 126 22 t j 5 8 hz 122 71 t j 22 0 hz 120 59 s 113 13 s 110 82 t j 117 7 hz 55 59 s 19 f nmr 376 mhz cdcl 3 u03b4 u2212 115 84 d j 55 7 hz the reaction was performed according to the general procedure for difluoromethylation on a 0 5 mmol scale 159 mg 1j the crude mixture was purified by silica gel chromatography 6 1 hexanes ethyl acetate r f 0 13 to give 2j 63 mg 52 yield 1 h nmr 500 mhz cdcl 3 u03b4 7 54 d j 8 1 hz 2h 7 31 d j 8 1 hz 2h 6 67 t j 56 3 hz 1h 3 21 s 3h 1 04 s 9h 13 c nmr 126 mhz cdcl 3 u03b4 178 01 s 147 52 t j 2 0 hz 133 74 t j 22 7 hz 129 05 s 126 64 t j 5 9 hz 114 04 t j 239 2 hz 41 22 s 40 82 s 29 39 s 19 f nmr 376 mhz cdcl 3 u03b4 u2212 111 24 d j 56 3 hz the reaction was performed according to the general procedure for difluoromethylation on a 0 5 mmol scale 145 mg 1k the crude mixture was purified by silica gel chromatography 3 1 hexanes ethyl acetate r f 0 2 to give 2k 63 mg 59 yield a small amount lt 5 of unreacted 1k was unable to be separated from the product 1 h nmr 500 mhz cdcl 3.