370879-56-4

To a solution of (3aR,6aS)-2-benzyl octahydropyrrolo[3,4-c]pyrrole (10 g, 49.5 mmol) in tetrahydrofuran (THF, 100 mL) was sequentially added N,N-diisopropylethylamine (DIPEA, 12.8 g, 99 mmol) and di-tert-butyl dicarbonate (Boc2O, 10.8 g, 49.5 mmol). The reaction mixture was stirred at room temperature for 5 hours. After completion of the reaction, the reaction mixture was diluted with ethyl acetate and washed sequentially with water, saturated sodium bicarbonate (NaHCO3) solution and saturated saline. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford tert-butyl (3aR,6aS)-5-benzylhexahydropyrrolo[3,4-c]pyrrole-2(1H)-carboxylate as a yellow oil (12 g, 80%).

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