Diisopropylamine → (Cyclopropylethynyl)benzene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a degassed solution of iodobenzene (0.549 mL, 4.90 mmol), dichlorobis(triphenylphosphine)-palladium(II) (0.206 g, 0.294 mmol), copper(I) iodide (0.047 g, 0.245 mmol) and diisopropylamine (3.49 mL, 24.5 mmol) in N,N-dimethylformamide (20 mL) was added cyclopropylacetylene (0.622 mL, 7.35 mmol). The reaction mixture was heated to 75° C. for 45 minutes. The reaction mixture was then diluted with ethyl acetate (150 mL), washed with a 10% aqueous solution of lithium chloride (2×100 mL), washed with a 2M aqueous solution of ammonium hydroxide (100 mL), washed with brine (100 mL), and dried over anhydrous sodium sulfate. Concentration afforded a crude product which was purified by silica gel chromatography with hexanes/dichloromethane (10/1) to give (cyclopropylethynyl)benzene (691 mg). The compound had an HPLC ret. time=3.40 min.−Column. YMC S5 COMBISCREEN® 4.6×50 mm; Gradient time: 4 min; Flow rate=4 ml/min; Solvent A=10% MeOH−90% Water−0.2% H3PO4; Solvent B=90% MeOH−10% water−0.2% H3PO4; Start % B=0; Final % B=100.

Herkunft & Nachweise