Potassium Iodide → 1'-t-Butoxycarbonylspiro[benzo[c]thiophene-1-(3H),4'-piperidine]-2-oxide

Participants

Reaction Steps

42.0 g (0.14 mole) of 1'-t-butoxycarbonylspiro[benzo[c]thiophene-1(3H),4'-piperidine] [prepared as described in step (a) above] were dissolved in 420 ml of chloroform, and 12.7 g (0.15 mole) of sodium hydrogencarbonate were added thereto. 28.0 g (0.14 mole) of m-chloroperbenzoic acid (purity 85%) were then added little by little, whilst ice-cooling. The mixture was then stirred for 30 minutes, whilst ice-cooling, after which 10 g of potassium iodide were added, and the mixture was stirred for a further 30 minutes at room temperature. The reaction mixture was washed with water and then with a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate. At the end of this time, the solvent was removed by distillation under reduced pressure, and the resulting residue was purified by silica gel column chromatography, using a 1:1 by volume mixture of hexane and ethyl acetate as the eluent, to give 42 g of the title compound as white crystals, melting at 103-107° C. (after crystallisation from diisopropyl ether).

Provenance & Evidence