159991-07-8

The general procedure for the synthesis of tert-butyl (4aS,7aS)-octahydro-1H-pyrrolo[3,4-b]pyridine-1-carboxylate from the compound (CAS: 159991-06-7) is as follows: Scheme 9: Preparation of [1S,6S]-2- tert-butoxycarbonyl-2,8-diazabicyclo[4,3,0]nonane 1. [1S,6S]-8-benzyl-2-tert-butoxycarbonyl-2,8-diazabicyclo[4,3,0]nonane (target product of embodiment 5, 5.0 g, 15.8 mmol) was dissolved in methanol (50 mL). 2. 10% Pd/C (1.0 g) was added as a catalyst at 3 atm and the hydrogenation reaction was carried out for 10 hours. 3. After completion of the reaction, the catalyst was removed by filtration. 4. 4. The filtrate was concentrated and the product was solidified by the addition of petroleum ether. 5. 5. Filtering and drying the obtained filter cake gave [1S,6S]-2- tert-butoxycarbonyl-2,8-diazabicyclo[4,3,0]nonane (3.1 g, 86.8% yield). Product Characterization: - Specific optical rotation:[α]20D = -70.2° (c = 4). - 1H NMR (CDCl3) δ: 1.45 (9H, s), 1.66-1.70 (2H, m), 2.03-2.11 (2H, m), 2.72-2.88 (2H, m), 3.11-3.78 (5H, m), 3.92-3.97 (1H, m), 4.53-4.55 (1H, m). - Mass Spectrometry (MS): m/z 227 (M++1).

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