反应详情

Concentrated hydrochloric acid (28.4 mL, 341 mmol) was added to a suspension of 3,7-dibenzyl-3,7-diazabicyclo[3.3.0]octan-2,4-dione (109.0 g, 341 mmol; from step (a) above) in CH3OH under a N2 atmosphere. To the resulting solution there was added 10% Pd/C (w/w; 5 g). The N2 atmosphere was exchanged for H2 (1 atm of pressure) and the reaction was stirred for 12 h. The reaction was diluted with H2O (160 mL), filtered through a pad of cellulose to remove the catalyst and the filtrate concentrated in vacuo to afford a solid. Triturating with absolute EtOH afforded 74.6 g (82%) of the sub-title compound as an off-white solid after drying in a vacuum oven at 50° C./66.5 Pa (0.5 mm Hg).

1. filtrationfiltered through a pad of cellulose
2. customto remove the catalyst
3. concentrationthe filtrate concentrated in vacuo
4. customto afford a solid
5. customTriturating with absolute EtOH