Hydrogen Bromide → 9-Bromo camptothecin

Participants

Reaction Steps

2.15 g of NaNO2 in 40 mL of H2O were dropped at 5° C. into a solution of 9 g of 9-amino-camptothecin in 850 mL of 16% HBr. After 1 hr at room temperature the solution was dropped in a flask containing 19 g of CuBr in 200 mL of 16% HBr at 70° C. The reaction mixture was kept at 70° C. for 2 hrs, then it was poured into cold water. The precipitate was filtered and the mother liquors were extracted with CH2Cl2; the organic extract, dried and evaporated, was combined with the precipitate and purified by flash chromatography (eluent:CH2Cl2/CH3OH=95/5) to give 8.19 g of the title product (HPLC assay:97.3%).

Provenance & Evidence