Sodium Methoxide → 1-[(1Z)-1-(methylsulfanyl)prop-1-en-2-yl]-3-(4-nitrobenzyl)-1,3-dihydro-2H-benzimidazol-2-one

Participants

Reaction Steps

163 mg of 3-methyl-9-(4-nitrobenzyl)[1,3]thiazolo[3,2-a]benzimidazol-9-ium chloride (0.450 mmol) were solubilised in methanol (30 mL), then 122 mg (5 eq) of NaOMe were added and the solution stirred at room temperature. After 48 h the solvent was evaporated, water was added (20 mL) and the mixture extracted with CH2Cl2 (3×20 mL). The organic layer was dried with MgSO4 and evaporated under reduced pressure to afford 1-[(1Z)-1-(methylsulfanyl)prop-1-en-2-yl]-3-(4-nitrobenzyl)-1,3-dihydro-2H-benzimidazol-2-one as a pale yellow oil (140 mg, 91%). Rf=0.59 (CH2Cl2/AcOEt 8:2); 1H NMR (300 MHz, CDCl3) δ=2.18 (3H, d, J=1.1, CH3), 2.27 (3H, s, SCH3), 5.19 (2H, brs, CH2), 6.29 (1H, q, J=1.1, H5), 6.77-6.85 (1H, m, Ar), 6.88-6.96 (1H, m, Ar), 6.98-7.14 (2H, m, Ar), 7.42-7.52 (2H, m, Ar), 8.12-8.23 (4H, m, Ar); 13C NMR (75 MHz, CDCl3) δ=16.88, 20.40, 44.09, 108.04, 109.35, 121.75, 121.82, 124.02 (2C), 126.23, 127.74, 128.03 (2C), 128.15, 128.90, 143.60, 147.48, 152.12; HRMS m/z C18H18N3O3S [M+H]+ calcd: 356.1063, found: 356.1067.

Provenance & Evidence