[Br:1][C:2]1[CH:3]=[C:4]([CH:7]=[C:8](/[CH:11]=[CH:12]/[CH2:13][O:14][CH3:15])[C:9]=1[CH3:10])[CH:5]=O.[CH:16]1([NH2:19])[CH2:18][CH2:17]1.[O-]S([O-])(=O)=O.[Mg+2].[BH4-].[Na+]>C(Cl)Cl.CO>[Br:1][C:2]1[CH:3]=[C:4]([CH:7]=[C:8](/[CH:11]=[CH:12]/[CH2:13][O:14][CH3:15])[C:9]=1[CH3:10])[CH2:5][NH:19][CH:16]1[CH2:18][CH2:17]13-Bromo-5-[(1E)-3-methoxy-1-propen-1-yl]-4-methylbenzaldehyde (1 eq.) from the previous step and cyclopropylamine (2 eq.) were combined in CH2Cl2 (0.1 M). To this was then added MgSO4 (1 eq.) and the resulting suspension was stirred at RT for 20 h. The insolubles were then removed via filtration through a pad of celite and the filtrate was concentrated in vacuo. The crude imine thus obtained was then re-taken up in MeOH (0.1 M). To this solution was added sodium borohydride (1.5 eq.) portionwise and the resulting mixture was stirred at 0° C. for 30 min, then at RT for 2 h. The reaction was quenched by stirring with 2 N aq. HCl for 25 min, basified with 1 N aq. NaOH and concentrated in vacuo. The residue was extracted with ether from water, dried over Na2SO4, filtered and the filtrate concentrated in vacuo to afford the title compound as a colorless oil.
Wird geladen…