1,8-Diazabicyclo(5.4.0)undec-7-ene → 4-Fluoro-7-methoxy-1-benzothiophene

Temperature

200 °C

4-Fluoro-7-methoxy-1-benzothiophene-2-carboxylic acid (2.00 g, 8.84 mmol) was added in one portion to DBU (8 mL) and dimethyl acetamide (10 mL). This was heated in the microwave with 300 W at 200° C. for 1 h. The reaction mixture was allowed to cool and poured onto water (100 mL). Product was extracted with hexane (2×100 mL), washed with aqueous hydrochloric acid (2 N, 50 mL), aqueous sodium hydroxide (2 N, 50 mL), and the combined organic extracts were dried (MgSO4) and concentrated in vacuo. The residue was purified by flash chromatography eluting silica gel with hexane:ethyl acetate [96:4] to give an oil (1.12 g, 70%): δH (300 MHz, CDCl3) 7.4 (2H, s, Ar), 6.9 (1H, t, Ar), 6.60 (1H, dd, Ar), 3.91 (3H, s, OCH3).

1. temperatureto cool
2. additionpoured onto water (100 mL)
3. extractionProduct was extracted with hexane (2×100 mL)
4. washwashed with aqueous hydrochloric acid (2 N, 50 mL), aqueous sodium hydroxide (2 N, 50 mL)
5. dry with materialthe combined organic extracts were dried (MgSO4)
6. concentrationconcentrated in vacuo
7. customThe residue was purified by flash chromatography
8. washeluting silica gel with hexane

ORD record

ord-b521eb4d6b2d4063981879ba71133837

Source dataset

uspto-grants-2008_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07410982B2