Methyl iodide → 4-(Methylthio)-5,6-dihydrofuro[2,3-h]quinazolin-2-amine

Participants

Reaction Steps

A solution of 6,7-dihydro-4(5H)-benzofuranone (0.10 g, 0.73 mmol), carbon disulfide (0.048 mL, 0.80 mmol), and iodomethane (0.10 mL, 1.6 mmol) in tetrahydrofuran (1.8 mL) was treated with a 60% dispersion of sodium hydride in mineral oil (0.070 g, 1.8 mmol), stirred over night at ambient temperature and partitioned between saturated ammonium chloride and ethyl acetate. The organic layer was washed with brine, dried (magnesium sulfate), filtered and concentrated. The residue was treated with guanidine nitrate (0.36 g, 2.9 mmol), treated with 1.46 mL (2.2 mol) of 1.5 M sodium ethoxide in ethanol, heated to 80° C. overnight, cooled, diluted with water and extracted with dichloromethane (3×). The combined dichloromethane layers were dried (magnesium sulfate), filtered, concentrated and chromatographed using ethyl acetate in dichloromethane to provide the title compound: 1H NMR (300 MHz, CDCl3) δ 2.52 (s, 3H), 2.88-3.02 (m, 4H), 5.07 (br s, 2H), 6.87 (d, J=1.7 Hz, 1H), 7.37 (d, J=2.0 Hz, 1H); MS (DCI/NH3) m/z 234 (M+H)+.

Provenance & Evidence