3-Chloro-benzamidine → 2-(3-chlorophenyl)-1,6,7,8-tetrahydrothiopyrano[3,2-d]pyrimidin-4-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-chlorobenzimidamide (4.3 g, 27.7 mmol) in ethanol (120 mL) was added methyl 3-oxotetrahydro-2H-thiopyran-2-carboxylate (4.82 g, 27.7 mmol) and sodium methoxide (1.8 g, 33.2 mmol). The mixture was stirred at 85° C. for 16 h. After this time, the mixture was concentrated after which ethanol (10 mL) was added and the suspension was chilled to 0° C. HCl (2 M, 50 mL) was added and the suspension was filtered and washed with water. The solid was dried under heat and vacuum to afford the title compound (5.2 g, 67%) as a light yellow solid. MW=278.75. 1H NMR (DMSO-d6, 500 MHz) δ 12.81 (s, 1H), 8.12 (s, 1H), 8.03 (d, J=7.5 Hz, 1H), 7.63-7.58 (m, 1H), 7.56-7.51 (m, 1H), 3.01-2.95 (m, 2H), 2.74 (t, J=6.0 Hz, 2H), 2.12-2.04 (m, 2H); APCI MS m/z 279 [M+H]+.

Provenance & Evidence