反应详情

C10 (3.5 g, 15.8 mmol) is added to a suspension of triphenylphosphine (166 mg, 0.63 mmol) and palladium acetate (71 mg, 0.32 mmol) in 25 mL DMF in dry flask under N2. Propioaldehyde diethyl acetal (2.3 mL, 15.8 mmol), cuprous iodide (120 mg, 0.63 mmol), and piperidine (1.6 mL, 16 mmol), are added successively, and the reaction is stirred 6 h at rt. The mixture is diluted with 125 mL EtOAc, is extracted with 4×50 mL 50% saturated 1:1 NaCl/NaHCO3, and the organic layer is dried over anhydrous Na2SO4 and then filtered. The dried organic layer is concentrated in vacuo to a dark oil. The crude material is chromatographed over 40 g silica gel (Biotage), eluting with 50% EtOAc/hexane. The fractions with the desired compound are combined and concentrated to afford 2-(diethoxymethyl)furo[3,2-c]pyridine (C11) (64% yield). HRMS (FAB) calculated for C12H15NO3+H: 222.1130, found 222.1123 (M+H)+.

1. extractionis extracted with 4×50 mL 50% saturated 1:1 NaCl/NaHCO3
2. dry with materialthe organic layer is dried over anhydrous Na2SO4
3. filtrationfiltered
4. concentrationThe dried organic layer is concentrated in vacuo to a dark oil
5. customThe crude material is chromatographed over 40 g silica gel (Biotage)
6. washeluting with 50% EtOAc/hexane
7. concentrationconcentrated