Carbon Dioxide → HCID 9990085, compound

Temperature

-30 °C

A solution of 43 (3.0 g, 14.4 mmol) and TMEDA (2.6 ml, 17.3 mmol) in THF (40 ml) was cooled to −50° C., and dropwise and slowly added with sec-BuLi (1.3 M in cyclohexane, 13.3 ml, 17.3 mmol). The reaction mixture was warmed to −30° C., and then cooled again to −60° C., and dry ice was added to the mixture. The reaction mixture was warmed to room temperature over 1 hour, added with waster (50 ml) and ethyl acetate (50 ml). The aqueous layer was separated, acidified with 2N HCl to pH 3-4, and extracted with ethyl acetate (100 ml). The organic layer was washed with water (50 ml) and saturated brine (50 ml), and dried. The solvent was removed in vacuo. The residue was dissolved in toluene (50 ml), added with p-TsOH.H2O (250 mg), and heated to reflux for 15 minutes. The reaction mixture was cooled to room temperature and poured into an aqueous diluted sodium bicarbonate solution (60 ml). The organic layer was separated and washed with saturated brine (60 ml). After drying, the solvent was removed in vacuo, and the residue was purified by column chromatography to yield 1.02 g (37%) of 44. 1H NMR (CDCl3) δ: 1.40 (9H, s, tBu), 3.71 (2H, s, CH2), 7.02-7.27 (3H, m, 3×Ar—H).

1. temperaturecooled again to −60° C.
2. temperatureThe reaction mixture was warmed to room temperature over 1 hour
3. customThe aqueous layer was separated
4. extractionextracted with ethyl acetate (100 ml)
5. washThe organic layer was washed with water (50 ml) and saturated brine (50 ml)
6. customdried
7. customThe solvent was removed in vacuo
8. dissolutionThe residue was dissolved in toluene (50 ml)
9. additionadded with p-TsOH.H2O (250 mg)
10. temperatureheated
11. temperatureto reflux for 15 minutes
12. temperatureThe reaction mixture was cooled to room temperature
13. additionpoured into an aqueous diluted sodium bicarbonate solution (60 ml)
14. customThe organic layer was separated
15. washwashed with saturated brine (60 ml)
16. customAfter drying
17. customthe solvent was removed in vacuo
18. customthe residue was purified by column chromatography

ORD record

ord-14ae0d9454ee4582b2a481ceba180f58

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06743923B2