1,3-Dibromopropane → 5-Bromo-2-(3,4-dimethoxyphenyl)-2-isopropylpentanenitrile

Temperatur

-30 °C

To a solution of 11.21 g (51.1 mmol) of 2-(3,4-dimethoxyphenyl)-3-methylbutanenitrile in 126 mL of tetrahydrofuran (THF) at −30° C., was slowly added 46.0 mL (46.0 mmol) of sodium bis(trimethylsilyl)amide (NaHMDS, 1.0 M in THF). The mixture was stirred at −30° C. for 10 minutes and 9.40 mL (256 mmol) of 1,3-dibromopropane was added dropwise. The mixture was warmed to 22° C. and stirred for about 16 h. A saturated aqueous solution of NH4Cl was then added and the mixture was extracted with ethyl acetate. The organic layer was washed with brine, dried (Na2SO4), filtered and evaporated. The residue was purified by flash chromatography on silica gel eluting first with hexane and then gradually increasing to 15% ethyl acetate/hexane to give 5-bromo-2-(3,4-dimethoxyphenyl)-2-isopropylpentanenitrile as an oil.

1. customat −30° C.
2. temperatureThe mixture was warmed to 22° C.
3. stirringstirred for about 16 h
4. extractionthe mixture was extracted with ethyl acetate
5. washThe organic layer was washed with brine
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. customevaporated
9. customThe residue was purified by flash chromatography on silica gel eluting first with hexane
10. temperaturegradually increasing to 15% ethyl acetate/hexane

ORD-Eintrag

ord-10e46017d7674332baeb174f1751786b

Quelldatensatz

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09227918B2