Sodium hydride → 5-Dimethylthiocarbamoyloxy-benzofuran-2-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 5-hydroxy-benzofuran-2-carboxylic acid methyl ester (2 g, 10 mmol) in 50 mL dry DMF was treated portionwise with NaH (252 mg of a 95% dispersion in mineral oil, 10 mmol). After 30 min, dimethylthiocarbamoyl chloride (1.9 g, 15 mmol) was added and the reaction stirred at 40° C. for 1.5 hours. The reaction mixture was then concentrated in vacuo, and the residue taken up in EtOAc. The organic layer was then washed 1×water, 1×brine, dried (Na2SO4) and the solvent removed in vacuo to give 3.5 g of the crude title compound. Recrystallization from CHCl3/hexanes, gave 1.3 g (45%) of the title compound. 400 MHz 1H NMR (DMSO-d6) δ 7.72 (s, 1H), 7.68 (d, 1H, J=9.8 Hz), 7.43 (s, 1H), 7.17 (d, 1H,J=9.8 Hz), 3.85 (s, 3H), 3.32 (s, 3H), 3.29 (s, 3H).

Provenance & Evidence