Diisopropylamine → tert-Butyl (4R)-4,8-dimethylnonanoate

Temperatur

-78 °C

To diisopropyl amine (0.827 mL, 5.9 mmol) in THF (8 mL) at −78° C. was added nBuLi (2.65 mL of a 2.6 M solution in pentane). The solution was stirred for 30 min at −78° C., followed by the addition of t-butyl acetate (0.8 mL, 5.9 mmol). The mixture was stirred at −78° C. for 2 h, and then (R)-1-iodo-2,6-dimethyl heptane (0.3 g, 1.18 mmol) and HMPA (1.5 mL) in THF (1 mL) was added. The reaction was stirred at −78° C. and allowed to slowly reach ambient temperature overnight, then heated at 35° C. to drive the reaction to completion. The reaction was quenched by the addition of ammonium chloride (saturated aqueous solution), and the mixture was extracted with EtOAc (2×10 mL). The organics were combined, washed with water, dried (MgSO4), filtered and concentrated. Silica gel chromatography (98/2 hexane/EtOAc) provided 0.25 g of (4R)-4,8-dimethyl nonanoic acid t-butyl ester.

1. stirringThe mixture was stirred at −78° C. for 2 h
2. stirringThe reaction was stirred at −78° C.
3. customallowed to slowly reach ambient temperature overnight
4. temperatureheated at 35° C.
5. customthe reaction to completion
6. customThe reaction was quenched by the addition of ammonium chloride (saturated aqueous solution)
7. extractionthe mixture was extracted with EtOAc (2×10 mL)
8. washwashed with water
9. dry with materialdried (MgSO4)
10. filtrationfiltered
11. concentrationconcentrated

ORD-Eintrag

ord-a13be158e5914198bcadb8459976a690

Quelldatensatz

uspto-grants-2008_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07419981B2