Dimethylformamide → N-tert-Butyl-3-formyl-5,5-dimethyl-5,6-dihydro-4H-cyclopenta[b]thiophene-2-carboxamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 282e (1.5 g, 6.0 mmol) in anhydrous THF (60 mL) cooled at −70° C. was added the solution of n-butyl lithium (10.0 mL, 25 mmol, 2.5 Min hexane) over a period of 5 minutes. It was stirred at −70° C. for 6 h. DMF (1.3 g, 18.0 mmol) was added over a period of 5 minutes and the result mixture was stirred at room temperature for overnight. It was then quenched with saturated NH4Cl (40 mL) and concentrated under reduced pressure. The residue was extracted with ethyl acetate (2×30 mL). The combined organic layer was dried over anhydrous Mg2SO4 and filtered. The filtrate was evaporated under reduced pressure to afford 282f as yellow solid (1.34 g, 80%). MS-ESI: [M+H]+ 280.3

Provenance & Evidence