Triethylamine → 2-[(Trimethylsilyl)ethynyl]benzaldehyde

Beteiligte Stoffe

Reaktionsschritte

A solution of 2-bromo-benzaldehyde (20.0 g, 108.1 mmol) in anhydrous tetrahydrofuran (200 mL) was degassed with argon for 30 minutes at room temperature. To the above solution was added bis(triphenylphosphine)palladium(II) chloride (Pd(PPh3)2Cl2) (3.79 g, 5.4 mmol) and the mixture was degassed again for an additional 15 minutes. To the reaction mixture were added trimethylsilanyl acetylene (33.97 mL, 216.2 mmol), copper(I) iodide (1.0 g, 5.4 mmol) and triethylamine (29.5 mL, 216.2 mmol), and the mixture was stirred for 16 hours at room temperature. Tetrahydrofuran was removed in vacuo. To the residue was added water (100 mL), and the resulting mixture was extracted with ethyl acetate (3×100 mL). The combined organic layers were dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give a black colored crude product. Flash chromatography (silica gel, 100-200 mesh, 2-5% ethyl acetate in hexane) afforded 2-trimethylsilanylethynyl-benzaldehyde (18.0 g, 82%) as a brown colored solid. MS (ESI+) cald. for C12H14OSi [(M+H)+] 202, obsd. 203.

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