反应详情

温度

0 °C

Under argon, 1.00 g (2.72 mmol) of the compound from example 6A was initially charged in pyridine (55 ml), the mixture was cooled to 0° C. and 228 μl (2.72 mmol) of methyl chloroformate (solution in 10 ml of dichloromethane) were then added dropwise. The reaction mixture was stirred further at RT overnight and then concentrated. The residue was triturated with ethanol and the solid was filtered off and dried at 50° C. under high vacuum. This gave 873 mg (75% of theory) of the title compound as a beige solid. The filtrate was re-concentrated, and purification by preparative RP-HPLC (acetonitrile:water (+0.1% formic acid)−gradient) of the residue gave a further 180 mg (16% of theory) of the title compound.

1. concentrationconcentrated
2. customThe residue was triturated with ethanol
3. filtrationthe solid was filtered off
4. customdried at 50° C. under high vacuum
5. concentrationThe filtrate was re-concentrated
6. custompurification by preparative RP-HPLC (acetonitrile:water (+0.1% formic acid)−gradient) of the residue