[S:1]1[C:5]2=[CH:6][N:7]=[CH:8][CH:9]=[C:4]2[CH:3]=[C:2]1[C:10]([O:12][CH3:13])=[O:11].[C:14](#N)C>[Pt](=O)=O.CO>[CH3:14][N:7]1[CH2:8][CH2:9][C:4]2[CH:3]=[C:2]([C:10]([O:12][CH3:13])=[O:11])[S:1][C:5]=2[CH2:6]1A solution of methyl thieno[2,3-c]pyridine-2-carboxylate (370 mg, 1.9 mmol) and acetonitrile (7.3 mL) was stirred at 42° C. for 6 h over which time the formation of a precipitate was observed. Upon cooling to room temperature, the solvent was removed in vacuo. To the material thus obtained was added methanol (10 mL) and platinum dioxide (100 mg, 0.4 mmol). The mixture was stirred under a balloon H2 atmosphere pressure for 4 h. The solvent was then removed under reduced pressure and the residue obtained was partitioned between EtOAc and saturated aqueous NaHCO3. Upon separation, the aqueous layer was extracted with EtOAc three additional times. The combined organic phases were further washed with saturated aqueous NaHCO3, water and brine, dried over anhydrous MgSO4 and concentrated to give methyl 6-methyl-4,5,6,7-tetrahydrothieno[2,3-c]pyridine-2-carboxylate (0.4 g, 95%) as an off-white solid. LCMS: (FA) ES+ 212; 1H NMR (CDCl3, 300 MHz) δ7.50 (s, 1 H ), 3.85 (s, 3 H ), 3.64 (m, 2H), 2.73 (m, 4 H ), 2.48 (s, 3 H ).
Wird geladen…
