Carbon Dioxide → HCID 19900818, compound

Temperature

-40 °C

A 1.55 M solution of butylithium in hexane (6.2 ml, 10 mmol) was added to a stirred solution of A (1.1 g, 5 mmol) in anhydrous tetrahydrofuran (30 ml) maintained at -40° C. under an atmosphere of argon. When the addition was complete, the mixture was stirred for 1 hour at -5° C. Isoamyl nitrate (2 ml, 15 mmol) was then added dropwise to the stirred mixture at -5° C. The reaction mixture was then stirred for a further 2 hours at -5° to 0° C. The mixture (containing lithium 2-(benzo[b]thien-5-ylthio)-2-nitroacetate) was acidified to pH 2 by addition of 2 M hydrochloric acid and was then left for 30 minutes at ambient temperature, after which time evolution of carbon dioxide (produced by decarboxylation of 2-(benzo[b]thien-5-ylthio)-2-nitroacetic acid) had ceased. Water (50 ml) was then added and the mixture was extracted with ethyl acetate. The combined extracts were washed successively with a saturated solution of sodium hydrogen carbonate, then with brine, dried (Na2SO4), and the solvent removed by evaporation. The residual oil was purified by flash chromatography using 75:25 v/v hexane/toluene as eluant to give 5-(nitromethylthio)benzo[b]thiophene as a yellow oil; NMR (90 MHz): 5.5 (s,2H), 7.2-8.0 (m,5H); m/e (electron impact); 225 (M+).

1. additionWhen the addition
2. stirringThe reaction mixture was then stirred for a further 2 hours at -5° to 0° C
3. waitwas then left for 30 minutes at ambient temperature
4. extractionthe mixture was extracted with ethyl acetate
5. washThe combined extracts were washed successively with a saturated solution of sodium hydrogen carbonate
6. dry with materialwith brine, dried (Na2SO4)
7. customthe solvent removed by evaporation
8. customThe residual oil was purified by flash chromatography

ORD record

ord-0c93705e01a64db79c0a0ab4041849f8

Source dataset

uspto-grants-1992_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05102905