反应详情

Toluene (700 mL), mercaptoacetic acid (38 mL, 50.03 g, 0.543 mol), and p-toluenesulfonic acid (1.0 g) were added to a solution of glyoxylic acid monohydrate (50.0 g, 0.543 mol) in 200 mL of THF in a 2 L round bottom flask equipped with a Dean-Stark trap and condenser. The resultant reaction mixture was refluxed for 3 hours until 24.0 mL of H2O was azeotropically removed. The reaction mixture was cooled, followed by removal of solvent under reduced pressure to yield an off-white solid. This material was purified by recrystallization (hexanes-EtOAc) to give 60.0 g of the product as a crystalline white solid: m.p. 140°-143° C.; 1H NMR (DMSO) δ 3.84 (q, 2H, JAB=16.7 Hz), 6.00 (s, 1H).

1. customequipped with a Dean-Stark trap and condenser
2. customThe resultant reaction mixture
3. customwas azeotropically removed
4. temperatureThe reaction mixture was cooled
5. customfollowed by removal of solvent under reduced pressure
6. customto yield an off-white solid
7. customThis material was purified by recrystallization (hexanes-EtOAc)