Methane → Tonapofylline

Participants

Reaction Steps

3-[4-(2,6-Dioxo-1,3-dipropyl-2,3,6,7-tetrahydro-1H-purin-8-yl)-bicyclo[2.2.2]oct-1-yl]-acrylic acid, (XIII, Example 89, 1.934 kg), tetrahydrofuran (11.875 l), water (0.625 l) and activated charcoal (0.100 kg) are mixed and stirred at 16 to 25° for 30 minutes and then filtered. The filter cake is washed with THF (0.500 l). A separate flask is charged with palladium on carbon (10%, 0.130 kg) and the filtered tetrahydrofuran/water mixture of the starting material. The flask is placed under reduced pressure and purged with nitrogen. The reduced pressure/nitrogen purge is repeated twice. The flask and contents are placed under reduced pressure and purged twice with hydrogen. The mixture is vigorously stirred under an atmosphere of hydrogen at 20° C. for 3 hours. The reaction vessel is evacuated and purged with nitrogen three times. The contents are filtered through celite (0.500 kg) and the filter cake washed with tetrahydrofuran (2×0.500 l). The solvent is removed under reduced pressure at 40 to 45°. Aqueous acetonitrile (50%, 7.540 l) is added to the residue and the slurry is aged at 15 to 25°, with stirring, for 3 hours. The slurry is cooled to between 0 and 5° and filtered. The filter cake is washed with aqueous acetonitrile (50%, 1.93 l), transferred to drying trays and dried at 50 to 60° under reduced pressure for 24 hours to give the title compound.

Provenance & Evidence