Sodium Carbonate → 4-(4-Nitro-phenyl)-3,6-dihydro-2H-thiopyran

Participants

Reaction Conditions

Reaction Steps

To a mixture of 4-nitrophenylboronic acid (418 mg, 2.50 mmol), trifluoromethanesulfonic acid 3,6-dihydro-2H-thiopyran-4-yl ester (as prepared in the previous step, 931 mg, 3.75 mmol), Pd(PPh3)4 (433 mg, 0.375 mmol) and lithium chloride (LiCl) (212 mg, 5.0 mmol) in 20 mL of 1,4-dioxane was added 2.0 M aq Na2CO3 solution (3.13 mL, 6.25 mmol). The resulting mixture was stirred at 80° C. for 2 h and then cooled to RT. Treated with 200 mL of EtOAc, the mixture was washed with H2O (2×30 mL), brine (30 mL) and dried (Na2SO4). Removal of the solvent under reduced pressure followed by flash chromatography of the residue on silica gel (1-3% EtOAc/hexane) gave 470 mg (85%) of the title compound as a light brown oil. 1H-NMR (CDCl3; 400 MHz): δ 8.19 (d, 2H, J=9.1 Hz), 7.48 (d, 2H, J=9.1 Hz), 6.36 (m, 1H), 3.39 (m, 2H), 2.91 (t, 2H, J=5.7 Hz), 2.72 (m, 2H). Mass spectrum (ESI, m/z): Calcd. for C11K1NO2S, 222.1 (M+H). found 222.3.

Provenance & Evidence