Methyl 4-nitrobenzoate → 1-(4-Nitrophenyl)-2,2,2-trifluoroethane-1,1-diol

Temperatur

-78 °C

To a mixture of 4-nitro-benzoic acid methyl ester (1.8 g, 9.9 mmol), trimethyl-trifluoromethyl-silane (2.0 ml, 12.8 mmol) and anhydrous dichloromethane (20 ml), cooled at −78° C., was added a solution of tetrabutylammonium fluoride in dichloromethane (1 M, 0.5 ml) previously dried over 4A molecular sieves. After stirring for 72 hours, hydrochloric acid (1 M, 50 ml) was added. The mixture was treated with saturated aqueous sodium chloride solution (100 ml) and extracted with ethyl acetate (100 ml). The organic extract was concentrated under reduced pressure. The residue was purified by flash chromatography on silica gel eluting with ethyl acetate-hexane (1:3) providing 2,2,2-trifluoro-1-(4-nitro-phenyl)-ethane-1,1-diol (1.1 g, 47% yield).

1. dry with materialpreviously dried over 4A molecular sieves
2. additionhydrochloric acid (1 M, 50 ml) was added
3. additionThe mixture was treated with saturated aqueous sodium chloride solution (100 ml)
4. extractionextracted with ethyl acetate (100 ml)
5. extractionThe organic extract
6. concentrationwas concentrated under reduced pressure
7. customThe residue was purified by flash chromatography on silica gel eluting with ethyl acetate-hexane (1:3)

ORD-Eintrag

ord-22b8025c6fed4512a99f7b5726576bc2

Quelldatensatz

uspto-grants-2008_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07419984B2