4-Toluenesulfonyl chloride → HCID 12041750, compound

Participants

Reaction Steps

To a solution of ethyl 7-hydroxy-8-nitro-4-oxochromen-2-carboxylate [J.Chem. Soc. (c), 1970, 2609] ( (5.58 g, 0.02 mol) in anhydrous THF (100 mL) was added p-toluenesulfonyl chloride (7.63 g, 0.04 mol) and K2CO3 (5.52 g, 0.04 mol). The reaction mixture was allowed to stir for 12 hours at room temperature. The solution was filtered, and the filtrate was diluted with EtOAc (200 mL) and washed sequentially with saturated NaHCO3 solution (30 mL) and water (2×30 mL), dried over anhydrous Na2SO4, and filtered. The solvent evaporated to give a white solid which was recrystallized from EtOAc-hexane (1:1) to give 8.15 g (94%) of the title compound: mp 125° C.; 1H NMR (400 MHz, CDCl3): 1.39 (t, J=7Hz, 3H), 2.48, (s, 3H), 4.42 (q, J=7.0 Hz, 2H), 7.14 (s, 1H), 7.38 (d, J=9 Hz, 1H), 7.67 (d, J=9 Hz, 1H), 7.80 (d, J=9 Hz, 2H), 8.33 (d, J=9 Hz); IR: 3450, 3080, 2980, 1740, 1670, 1610, 1540, 1490, 1230 cm−1; MS 451[M+NH4].

Provenance & Evidence