反应详情

A mixture of 2,5-dimethoxybenzoic acid (25 g, 137.2 mmol) and thionyl chloride (35 mL, 470.6 mmol) was heated at reflux under Ar for 4 h. The reaction solution was evaporated to dryness and the residue was purified by high vacuum distillation at 127° C./2 mm Hg to give compound 45 as a pale yellow oil (26.5 g, 96.7%). When standing at room temperature, this oil changed to yellow crystals, m.p. 36°-38° C.

1. temperaturewas heated
2. temperatureat reflux under Ar for 4 h
3. customThe reaction solution was evaporated to dryness
4. distillationthe residue was purified by high vacuum distillation at 127° C./2 mm Hg