Acetic Acid → 5-bromo-3,3-dimethyl-2,3-dihydro-1H-inden-1-one

Temperature

60 °C

To a solution of 6-bromo-1,1-dimethyl-2,3-dihydro-1H-indene (3.6 g, 16 mmol) in acetic acid (50 mL) was added to a solution of CrO3 (9.6 g, 96.0 mmol) in 50% aqueous acetic acid (50 mL). This solution was heated for 3 h at 60° C. At completion, the reaction mixture was quenched by the addition of isopropanol (20 mL). The quenched reaction was partitioned between EtOAc (200 mL) and a 0.25 M aqueous NaOH (100 mL). The layers were separated and the organics were extracted with EtOAc (2×100 mL). The combined organics were washed with brine, dried over Na2SO4, filtered and concentrated. After purification by flash chromatography over silica gel (50% EtOAc/hexanes eluent), 5-bromo-3,3-dimethyl-2,3-dihydro-1H-inden-1-one (2.91 g, 76% yield) was isolated as a white solid. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 7.65 (s, 1H), 7.47-7.58 (m, 2H), 2.58 (s, 2H), 1.42 (s, 6H); MS (EI) m/z=240.1 [M+1]+.

1. customAt completion, the reaction mixture was quenched by the addition of isopropanol (20 mL)
2. customThe quenched reaction
3. customwas partitioned between EtOAc (200 mL)
4. customThe layers were separated
5. extractionthe organics were extracted with EtOAc (2×100 mL)
6. washThe combined organics were washed with brine
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customAfter purification by flash chromatography over silica gel (50% EtOAc/hexanes eluent)

ORD record

ord-20f9a408f1404a768bc6c64165daec43

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08440652B2