Chlorotriethylsilane → (difluoromethyl)triethylsilane

Participants

Reaction Steps

Into a mixture of 5 g (26 mmol) difluoromethyl phenyl sulfone (4), 1.9 g Mg turnings (78 mmol) and 150 mL DMF at −40° C., was slowly added 11.8 g (78 mmol) chlorotriethylsilane. The reaction mixture was then stirred at −40° C. to 10° C. during a 4 h period until 19F NMR indicated all of 4 was consumed. Similar work-up as above and fractional distillation gave 2.2 g product 19, b.p. 71° C./56 Torr, yield 51%. 1H NMR (500 MHz, CDCl3): δ0.72 (q, 3JH-H=8.0 Hz, 6H); 1.02 (t, 3JH-H=8.0 Hz, 9H); 5.95 (t, 2JH-F=46.0 Hz, 1H). 13C NMR (125 MHz, CDCl3): δ0.6 (s, CH2); 6.7 (s, CH3); 124.3 (t, 1JC-F=254.8 Hz). 19F NMR (470 MHz, CDCl3): δ−137.6 (d, 2JF-H=45.8 Hz). 29Si NMR (99 MHz, CDCl3): δ3.3 (t, 2JSi-F=24.8 Hz). GC-MS (m/z): 166 (M+); 115 (Et3Si+); 51 (CF2H+).

Provenance & Evidence