Potassium Permanganate → Spiro[cyclopropane-1,1'-[1H]inden]-3'(2'H)-one, 6'-bromo-

To a solution of 6′-bromo-2′,3′-dihydrospiro[cyclopropane-1,1′-indene] (5.7 g, 25.6 mmol) in acetone (78 mL) and 1.5 M aq. MgSO4 (29 mL) was added KMnO4 (4.46 g, 28.2 mmol). The reaction was stirred overnight at room temperature. Upon completion, the reaction was filtered over celite and concentrated. The residue was partitioned between water (100 mL) and EtOAc (200 mL), and the layers were separated. The organic was washed with brine, dried over Na2SO4, then filtered and concentrated. 6′-bromospiro[cyclopropane-1,1′-inden]-3′(2′H)-one (2.11 g, 39% yield) was isolated as a white solid after flash chromatography over silica gel (5% EtOAc/hexane eluent). 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 7.59 (d, J=8.3 Hz, 1H), 7.45 (dd, J=8.0, 1.5 Hz, 1H), 7.14 (d, J=1.3 Hz, 1H), 2.76 (s, 2H), 1.15-1.34 (m, 4H); MS (EI) m/z=238.1 [M+1]+.

1. filtrationUpon completion, the reaction was filtered over celite and
2. concentrationconcentrated
3. customThe residue was partitioned between water (100 mL) and EtOAc (200 mL)
4. customthe layers were separated
5. washThe organic was washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-06eaa15e565f49debf406d075ea67de0

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08440652B2