Carbon Dioxide → HCID 20260933, compound

Temperature

-78 °C

n-Butyl lithium (0.65 ml. of 1.55 M solution in hexane) was added dropwise to a stirred mixture of diisopropylamine (0.10 g.) and potassium t-butoxide (0.11 g.) in dry ether (10 ml.) at -78° C. under an atmosphere of dry nitrogen. The mixture was stirred at -78° C. for 45 minutes and then a solution of 3-methyl-6-(3-pyridylmethyl)benzo[b]thiophene (0.20 g.) in dry ether (5 ml.) was added. The solution was stirred at -78° C. for 45 minutes and then an excess of crushed solid carbon dioxide was added. When all the carbon dioxide had evaporated, water (5 ml.) was added and the mixture was shaken. The aqueous layer was then separated and washed with ether. It was then acidified with acetic acid and the solid was filtered off and dissolved in 2 N sodium hydroxide. The solution was decolorized by warming with charcoal and then filtered. Acidification of the filtrate with acetic acid gave a solid which was filtered off, washed with water and dried to give 3-methyl-6-(3-pyridylmethyl)-benzo[b]thiophene-2-carboxylic acid (0.10 g.), m.p. 250°-252° C.

1. stirringThe solution was stirred at -78° C. for 45 minutes
2. customWhen all the carbon dioxide had evaporated
3. additionwater (5 ml.) was added
4. stirringthe mixture was shaken
5. customThe aqueous layer was then separated
6. washwashed with ether
7. filtrationthe solid was filtered off
8. dissolutiondissolved in 2 N sodium hydroxide
9. temperatureby warming with charcoal
10. filtrationfiltered
11. customAcidification of the filtrate with acetic acid gave a solid which
12. filtrationwas filtered off
13. washwashed with water
14. customdried

ORD record

ord-b951f7061450458eba7a7b517a19e550

Source dataset

uspto-grants-1983_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04410539