C(OC([NH:8][C:9]1[CH:13]=[CH:12][S:11][C:10]=1[C:14]1[CH:19]=[CH:18][C:17]([Br:20])=[CH:16][CH:15]=1)=O)(C)(C)C.Cl.O.C([O-])(O)=O.[Na+]>CCOC(C)=O>[Br:20][C:17]1[CH:18]=[CH:19][C:14]([C:10]2[S:11][CH:12]=[CH:13][C:9]=2[NH2:8])=[CH:15][CH:16]=1
Treat dropwise a solution of (tert-butoxy)-N-[2-(4-bromophenyl)(3-thiophenyl)]carboxamide (10.8 g, 0.3 mol) in EtOAc (75 mL) at 0° C. with 244 mL (8 mL/mmol) of freshly prepared 1N HCl in EtOAc and stir the mixture at room temperature overnight. Dissolve the white precipitate with H2O (100 mL) and neutralize with a NaHCO3 saturated solution. Extract the mixture with EtOAc (3×100 mL) and combine organic, dry and concentrate to give a slightly colored solid. Purification of the crude material by flash chromatography (Silica gel-Hexane/AcOEt 49:1 then 9:1) furnishes 5.7 g (74%) of 2-(4-bromo-phenyl)-thiophen-3-yl amine as a pale yellow solid.
Wird geladen…
