Dimethyl Disulfide → 3-[Cyano-(3-ethyl-5-isopropyl-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidin-4-yl)-methyl]-5-methyl-benzonitrile

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Reaction Steps

To a stirred solution of 3-[cyano-(3-ethyl-5-isopropyl-1-methoxymethyl-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidin-4-yl)-methyl]-5-methyl-benzonitrile (190 mg, 0.5 mmol) in dichloromethane (5 mL) at room temperature, were added dimethyl disulfide (804 μL, 10 mmol) and boron trifluoride-diethyl etherate (300 μL, 2.37 mmol). After stirring for 3 days, the mixture was evaporated in vacuo and the residue was purified by silica gel column chromatography (eluent, ethyl acetate:hexane (1:1)) to give 150 mg (89%) of 3-[cyano-(3-ethyl-5-isopropyl-2,6-dioxo-1,2,3,6-tetrahydro-pyrimidin-4-yl)-methyl]-5-methyl-benzonitrile as a white solid. The product was recrystallized from chloroform-methanol-ether. m.p. 260-261° C.; 1H-NMR (200 MHz, DMSO-d6) δ 0.77 (3H, d, J=6.6 Hz), 1.07 (3H, t, J=7.0 Hz), 1.19 (3H, d, J=6.6 Hz), 2.41 (3H, s), 2.49 (1H, m), 3.68 (1H, m), 4.00 (1H, m), 6.22 (1H, s), 7.59 (1H, s), 7.71 (1H, s), 7.73 (1H, s), 11.45 (1H, s); m/z (EI) 336 (M+).

Provenance & Evidence