Triethylamine → 5,6-difluorobenzo[c][1,2,5]thiadiazole

To a solution of 4,5-difluorobenzene-1,2-diamine (2.0 g, 0.014 mol) and triethylamine (7.8 mL, 0.056 mol) in dichloromethane (80 mL) was added SOCl2 (4.04 mL, 0.055 mol) dropwise at room temperature. The resulting reaction mixture was heated to reflux overnight. The reaction mixture was then allowed to cool to room temperature, and quenched with water carefully. The resulting mixture was extracted with dichloromethane, dried over Na2SO4 and concentrated on a rotary evaporator to give a white solid as the crude compound. The crude product was purified by flash column chromatography (silica gel, hexanes) to afford 5,6-difluorobenzo[1,2,5]thiadiazole as a white crystalline solid (1.4 g, 58% yield). 1H NMR (CDCl3 500 MHz): δ: 7.76 (t, 2H, J=8.5 Hz). 13C NMR (CDCl3, 500 MHz): δ 154.94, 154.78, 152.86, 152.70, 150.89, 150.85, 150.81, 106.26, 106.21, 106.14, 106.09. Anal. calcd. for (C6H2F2N2S): C, 41.86; H, 1.17; N, 16.27. Found: C, 41.41; H, 1.22; H, 15.87. m.p: 64-65° C.

1. customThe resulting reaction mixture
2. temperaturewas heated
3. temperatureto reflux overnight
4. customquenched with water carefully
5. extractionThe resulting mixture was extracted with dichloromethane
6. dry with materialdried over Na2SO4
7. concentrationconcentrated on a rotary evaporator
8. customto give a white solid as the crude compound
9. customThe crude product was purified by flash column chromatography (silica gel, hexanes)

ORD record

ord-256899b095214dbaad78f4f1345853dd

Source dataset

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08723028B2