Phosphorus oxychloride → HCID 67536680, compound

3a,6a-Dihydro-thieno[3,2-b]thiophene-2-carboxylic acid amide 2 (4.0 g, 21.6 mmol) was mixed with 50 mL of POCl3 and the mixture was heated to reflux for 2 hours before POCl3 was removed with a rotary evaporator. Dichloromethane (100 mL) was added and then 100 mL of ice water was added dropwise. The organic layer was further washed with water (30 mL) twice before the solvent was removed. The brown oil obtained was passed through a short column of silica gel with dichloromethane as eluent. After removal of the solvent, a yellow oil was obtained (2.4 g, yield 67%). 1H NMR (CDCl3, 500 MHz): δ 7.80 (s, 1H), 7.72 (d, 1H, J=5.0), 7.30 (d, 1H, J=5.0); 13C NMR (CDCl3, 500 MHz): δ 143.39, 138.27, 133.52, 129.72, 119.38, 114.60, 110.27.

1. temperaturethe mixture was heated
2. customwas removed with a rotary evaporator
3. additionDichloromethane (100 mL) was added
4. addition100 mL of ice water was added dropwise
5. washThe organic layer was further washed with water (30 mL) twice before the solvent
6. customwas removed
7. customThe brown oil obtained
8. customAfter removal of the solvent
9. customa yellow oil was obtained (2.4 g, yield 67%)

ORD record

ord-0de801475cf54707936a2095b239cc36

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08598449B2