Dimethyl Sulfoxide → (1S,2R)-2-(4-chlorophenyl)spiro[cyclopropane-1,3'-indolin]-2'-one

Participants

Reaction Conditions

Reaction Steps

A solution of dimethylsulfoxoniummethylide was prepared as under argon from a 60% NaH mineral oil dispersion (88 mg, 2.2 mmol), trimethylsulfoxoniumiodide (484 mg, 2.2 mmol), and DMSO (10 mL). After 20 min, a solution of (Z)-3-(4-chloro-benzylidene)-1,3-dihydro-indol-2-one (510 mg, 2 mmol) in THF (5 mL) was added dropwise over 20 min. After stirring for 1 hour at room temperature and another 1 hour at 50° C., the solution was poured into ice-cold water (20 mL) and extracted with ether (3×20 mL). The combined ethereal extracts were washed with brine, dried and evaporated to an oil, which was purified by flash column chromatography (gradient elution, 15-25% ethyl acetate in petroleum ether to give the title compound as white solid (333 mg, 62%). LC/MS m/e calcd. for C16H12ClNO 269, observed (M+H)+:270.5. 1H NMR (400 MHz, DMSO-d6) δppm 1.95 (dd, J=8.97, 4.67 Hz, 1 H) 2.21 (dd, J=7.83, 4.80 Hz, 1 H) 3.04 (t, J=8.46 Hz, 1 H) 6.08 (d, J=7.58 Hz, 1 H) 6.59-6.71 (m, 1 H) 6.87 (d, J=7.58 Hz, 1 H) 7.01-7.10 (m, 1 H) 7.27-7.33 (m, 2 H) 7.33-7.40 (m, 2 H) 10.59 (s, 1 H).

Provenance & Evidence