反应详情

To a round-bottom flask is charged biphenyl-2,2′-diol (7.45 g, 40 mmol) and pyridine (50 mL). The flask is immersed in an ice-water bath and ethyl chloroformate (9.48 mL, 100 mmol) is added dropwise. After gradually warming to room temperature, the mixture is stirred overnight. The volatiles are removed in vacuo, and the residue is suspended in 100 mL of ethyl acetate. After filtration, the filtrate is concentrated and purified by flash chromatography. The product is obtained as a colorless oil. Yield: 5.0 g; 1H NMR (500 MHz, CDCl3, ppm) δ 7.23-7.44 (m, 8H), 4.13 (q, 4H), 1.19 (t, 6H).

1. customThe flask is immersed in an ice-water bath
2. customThe volatiles are removed in vacuo
3. filtrationAfter filtration
4. concentrationthe filtrate is concentrated
5. custompurified by flash chromatography
6. customThe product is obtained as a colorless oil