N-Methylbenzylamine → HCID 67517650, compound

Reaction equation

O=[C:2]1[CH2:8][O:7][CH2:6][CH2:5][N:4]([C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[CH2:3]1.[CH3:16][NH:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1.C(O[BH-](OC(=O)C)OC(=O)C)(=O)C.[Na+]>C(Cl)Cl>[CH2:18]([N:17]([CH3:16])[CH:2]1[CH2:8][O:7][CH2:6][CH2:5][N:4]([C:9]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10])[CH2:3]1)[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1

Participants

Procedure

A solution of tert-butyl 6-oxo-1,4-oxazepane-4-carboxylate (1.30 g (6.04 mmol) 107.1 (prepared as described in WO2004074291) in DCM (20 mL) was treated with N-methyl-benzylamine (0.857 mL, 6.64 mmol) and stirred at rt for 30 min. Sodium triacetoxyborohydride (1.54 g, 7.25 mmol) was then added, and the reaction mixture was stirred at room temperature for 24 hr. Excess hydride was quenched by the addition of H2O and the mixture was extracted with EtOAc (2×). The combined organic layers were dried with MgSO4, filtered, and concentrated in vacuo, absorbing onto 8 g SiO2. Purification by flash column chromatography (ISCO 40 g SiO2, 20% EtOAc/Hexanes then gradient to 80% EtOAc/hexanes) afforded tert-butyl 6-(benzyl(methyl)amino)-1,4-oxazepane-4-carboxylate (0.759 g) 107.2 as a clear oil. 1H NMR (400 MHz, CHLOROFORM-d) δ 7.35-7.28 (m, 4H), 7.27-7.19 (m, 1H), 4.19-4.10 (m, 1H), 4.06-4.03 (m, 1H), 3.99-3.95 (m, 1H), 3.87 (m, 1H), 3.77-3.75 (m, 2H), 3.64-3.56 (m, 1H), 3.50 (ddd, J=3.0, 9.9, 12.5 Hz, 1H), 3.26-3.12 (m, 2H), 3.11-2.98 (m, 1H), 2.33-2.22 (m, 3H), 1.53-1.33 (m, 9H); LCMS (ESI) m/z: 321.20 [M+H]+.