tert-Butyl hydroperoxide → HCID 17862545, compound

Participants

Reaction Steps

1-Oxo-1,3-dihydroisobenzofuran-5-carbonitrile (1.56 g, 9.78 mmol) obtained from in Example 4-(4) was suspended in tetrahydrofuran (15 ml), and an aqueous solution of sodium hydroxide (1.008N; 9.70 ml, 9.78 mmol) was added thereto. The mixture was stirred at room temperature for 15 minutes and the solvent was distilled off under reduced pressure. The residue was dried using a vacuum pump to give an amorphous solid. The solid was dissolved in N,N-dimethylformamide (30 ml), and 4-methoxybenzyl chloride (1.53 g, 9.78 mmol) was added thereto, and then the mixture was stirred at 80° C. for 5 minutes. After the mixture was cooled to 0° C., a saturated aqueous solution of ammonium chloride was added thereto, and the product was extracted with ethyl acetate. The organic layer was washed with water and with a saturated aqueous solution of sodium chloride, and the solvent was distilled off under reduced pressure to give an oily residue. The residue was dissolved in dichloromethane (50 ml), and tetrazole (1.40 g, 20 mmol) and bis(allyloxy)(diisopropylamino)phosphine (Tetrahedron Lett., 30, 4219 (1989); 3.43 g, 14 mmol) were added thereto at 0° C., and then the resulting mixture was stirred at the same temperature for 5 minutes. The mixture was warmed to room temperature and stirred for 20 minutes, and then methanol (0.5 ml) was added thereto. The mixture was stirred for 10 minutes and cooled to 0° C., and tert-butyl hydroperoxide (80% di-tert-butyl peroxide solution; Merck; 2.7 g, 24 mmol) was added thereto, and then the reaction mixture was warmed to room temperature followed by stirring 20 minutes. A saturated aqueous solution of sodium hydrogen carbonate and an aqueous solution of sodium thiosulfate were added to the reaction mixture, and the resulting mixture was stirred for 10 minutes and partitioned between ethyl acetate and water. The organic layers were combined and the solvent was distilled off under reduced pressure to give a residue. The residue was subjected to chromatography on a silica gel (120 g) column (eluent; ethyl acetate:hexane=2:3) to afford a mixture of a solid and an oily material. The mixture was washed with a mixed solvent of ethyl acetate-hexane, and the washings were concentrated to give a residue. The residue was subjected to chromatography on a silica gel (50 g) column (eluent; ethyl acetate:hexane=2:3) to afford the title compound (1.18 g, 26% yield) as a colorless oil.

Provenance & Evidence