[Si]([O:8][CH2:9][C:10]1[N:14]([CH3:15])[C:13]2[S:16][C:17]([C:19]3[C:28]([CH2:29][CH3:30])=[CH:27][C:22]([C:23]([O:25][CH3:26])=[O:24])=[C:21]([O:31][CH3:32])[N:20]=3)=[CH:18][C:12]=2[CH:11]=1)(C(C)(C)C)(C)C.CCCC[N+](CCCC)(CCCC)CCCC.[F-]>C1COCC1>[CH2:29]([C:28]1[C:19]([C:17]2[S:16][C:13]3[N:14]([CH3:15])[C:10]([CH2:9][OH:8])=[CH:11][C:12]=3[CH:18]=2)=[N:20][C:21]([O:31][CH3:32])=[C:22]([CH:27]=1)[C:23]([O:25][CH3:26])=[O:24])[CH3:30]To solution of methyl 6-(5-((tert-butyldimethylsilyloxy)methyl)-6-methyl-6H-thieno[2,3-b]pyrrol-2-yl)-5-ethyl-2-methoxynicotinate (0.594 g, 1.25 mmol) in THF (8 mL) was added solution of TBAF (1M THF, 1.50 mL, 1.50 mmol). Reaction mixture was stirred at room temperature for 30 min and THF was then concentrated. Residue was loaded directly on the column and product was isolated eluting with EtOAc/hexanes gradient (0-50%). Methyl 5-ethyl-6-(5-(hydroxymethyl)-6-methyl-6H-thieno[2,3-b]pyrrol-2-yl)-2-methoxynicotinate (0.233 g, 26% 2 steps) was obtained as solid.
Wird geladen…