Hydrochloric Acid → 3-Bromofuran-2-carboxylic acid

Temperature

-70 °C

To a mixture of 3-bromo furan (51.0 g; 0.347 mol) and THF (250 ml) was added lithiumdiisopropylamide (191 ml; 0.382 mol; 2 M solution in heptane/THF/ethylbenzene) at −70° C. The mixture was stirred for 1 hour at −70° C. Solid carbondioxide (100.3 g; 2.28 mol) was added and the mixture was stirred until the carbondioxide was gone. Water (50 ml) was addded followed by aqueous hydrochloric acid (380 ml; 2M). The tetrahydrofuran was evaporated. The mixture was extracted with diethylether (3×100 ml). The combined ether phase was extracted with aqueous sodium hydroxide (3×100 ml; 2M). The aqueous phase was cooled on ice and acidified with aqueous hydrochloric acid (100 ml; 10M). The mixture was extracted with ether (3×100 ml). The combined ether phase was evaporated. Yield 36 g (54%). Mp. 118.5° C.

1. additionSolid carbondioxide (100.3 g; 2.28 mol) was added
2. stirringthe mixture was stirred until the carbondioxide
3. customThe tetrahydrofuran was evaporated
4. extractionThe mixture was extracted with diethylether (3×100 ml)
5. extractionThe combined ether phase was extracted with aqueous sodium hydroxide (3×100 ml; 2M)
6. temperatureThe aqueous phase was cooled on ice
7. extractionThe mixture was extracted with ether (3×100 ml)
8. customThe combined ether phase was evaporated

ORD record

ord-59a92a38a93e49c1bd4ec5623467e7cd

Source dataset

uspto-grants-2010_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07678788B2