Diisopropylamine → HCID 19384667, compound

Temperature

-78 °C

n-Butyllithium (1.5 M, 20.7 mL) was added to a chilled (0° C.) solution of diisopropylamine (4.34 mL, 31 mmol) in tetrahydrofuran (60 mL). After 2-3 minutes, the flask was cooled to −78° C., and a solution of the product from Example 2, Step (a) (5.0 g, 28.2 mmol) in tetrahydrofuran (6 mL) was added over a three minute period. After allowing the yellow anion to stir for 40 minutes, 1-bromo-3-chloro-propane (3.06 mL, 31 mmol) was added, the bath was removed, and the mixture was allowed to stir at ambient temperature for 1 hour. Solvent was removed by rotary evaporation. The crude product was diluted with ether (150 mL) and the ether layer was washed with water (20 mL). The ether layer was dried using MgSO4 and concentrated. The residue was diluted with dichloromethane and filtered through a silica plug, rinsing with additional dichloromethane. Concentration afforded the title compound as an oil product characterized by NMR as follows: NMR(CDCl3, 400 MHz, partial): 3.48(m, 2h), 1.21(d, 3H, J=6 Hz), 0.78(d, 3H, J=6 Hz); 13CNMR(CDCl3, 100 MHz, partial): 52.8, 44.5, 38.0, 35.2, 28.5, 18.8, 18.5.

1. customthe bath was removed
2. stirringto stir at ambient temperature for 1 hour
3. customSolvent was removed by rotary evaporation
4. additionThe crude product was diluted with ether (150 mL)
5. washthe ether layer was washed with water (20 mL)
6. dry with materialThe ether layer was dried
7. concentrationconcentrated
8. additionThe residue was diluted with dichloromethane
9. filtrationfiltered through a silica plug
10. washrinsing with additional dichloromethane
11. concentrationConcentration

ORD record

ord-b9f2ba37be9f497d8a7a05ae54b81bcc

Source dataset

uspto-grants-2001_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06265439B1