反应详情

温度

55 °C

To a solution of tert-butyl 4-tert-butyl-2-vinyl-1-oxa-4,9-diazaspiro[5.5]undecane-9-carboxylate (550 mg, 1.62 mmol) in methanol (10 mL) was added Pd(OH)2 (447 mg, 3.18 mmol) and ammonium formate (2.19 g, 34.7 mmol) and the reaction mixture heated at 55° C. for 20 min. The reaction mixture was filtered, concentrated to −10 mL and then diluted with dichloromethane and 1:1 saturated NaHCO3 solution/1M NaOH. The dichloromethane layer was separated and the aqueous layer extracted with dichloromethane (5×20 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated in vacuo to provide tert-butyl 8-tert-butyl-10-ethyl-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate (530 mg, 1.56 mmol, 96%) as a colorless oil. ESI-MS m/z calc. 340.3. Found 341.3 (M+1)+; Retention time: 1.16 minutes (3 min run). 1H NMR (400 MHz, DMSO-d6) δ 3.59 (t, J=11.7 Hz, 2H), 3.48-3.36 (m, 1H), 3.11 (br s, 1H), 2.91 (br s, 1H), 2.80 (d, J=10.7 Hz, 1H), 2.71 (dd, J=11.1, 1.7 Hz, 1H), 2.23 (d, J=14.0 Hz, 1H), 1.81 (d, J=11.1 Hz, 1H), 1.71 (t, J=10.6 Hz, 1H), 1.39 (s, 9H), 1.38-1.22 (m, 5H), 0.96 (s, 9H), 0.89 (t, J=7.4 Hz, 3H).

1. filtrationThe reaction mixture was filtered
2. concentrationconcentrated to −10 mL
3. additiondiluted with dichloromethane and 1:1 saturated NaHCO3 solution/1M NaOH
4. customThe dichloromethane layer was separated
5. extractionthe aqueous layer extracted with dichloromethane (5×20 mL)
6. dry with materialThe combined organic layers were dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo