Yield:39549-22-9 51.4%

Reaction Conditions:

with sodium hydroxide in water at 20; for 16 h;

Steps:

1.1.1 1.1 Synthesis of intermediate compound A2

1.1 Synthesis of intermediate compound A2
Put together 2-ethoxyphenol (compound A1) (51.5g, 0.373mol) and 50% glyoxylic acid (37.3ml, 0.34mol, 1eq)and 100ml of distilled water. Add to a 500ml three-mouthed flask. Under ice-cooling, to the three-mouthed flask was added dropwise 10% NaOH solution(29.8gNaOH, 0.745mol, 300ml of distilled water 2eq). At room temperature react for 16 hours. washed with ethyl acetate (4 * 250ml) and the aqueous phase was adjusted pH = 2-3 with aqueous 6N hydrochloric acid , NaCl was added to saturation, and then extracted with ethyl acetate (3 * 200ml), the organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, andthe solvent under reduced pressure to give 51.4g spin dry brown solid, yield51.4%.

References:

CN105272871,2016,A Location in patent:Paragraph 0054; 0055; 0056; 0057; 0058