2-(2-trimethylsilylethynyl)benzaldehyde

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 2-trimethylsilanylethynyl-benzaldehyde (6 g, 29.70 mmol) in N,N-dimethylformamide (10 mL) was added potassium fluoride (1 g, 17.2 mmol). The reaction mixture was stirred at room temperature for 30 minutes. The resulting solution was poured into water, and then extracted with dichloromethane. The collected organic layers were dried over magnesium sulfate, filtered, and concentrated in vacuo. Flash chromatography (RediSep® Flash column, 230-400 mesh, 0-25% ethyl acetate in hexane) gave 2-ethynyl-benzaldehyde (2.8 g, 73%) as a white solid. MS (ESI+) cald for C9H6O [(M+H)+] 130, obsd. 131. extracted with dichloromethane The collected organic layers were dried over magnesium sulfate filtered concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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. the mixture was degassed again for an additional 15 minutes Tetrahydrofuran was removed in vacuo To the residue was added water (100 mL) the resulting mixture was extracted with ethyl acetate (3×100 mL) The combined organic layers were dried over anhydrous sodium sulfate filtered concentrated in vacuo to give a black colored crude product