Methyl iodide → 3-Methyl-5-[4-(trifluoromethyl)phenyl]thiophene-2-carbaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of trimethylethylenediamine (0.296 mL, 2.28 mmole) in THF at −78° C., is injected 2.0M n-butyllithium in cyclohexane (1.14 mL, 2.28 mmole) dropwise. The mixture is stirred for 15 minutes, then added a solution of 5-(4-Trifluoromethyl-phenyl)-thiophene-2-carbaldehyde (0.530 g, 2.07 mmole) in THF (5 mL) and stirred for another 15 minutes. To the resulting mixture is injected 2.0M n-butyllithium in cyclohexane (1.55 ml, 3.10 mmole) at −78° C. and warmed up to −18° C. for an hour. The reaction is cooled down to −78° C. again, quenched with excess amount of iodomethane (0.644 mL, 10.35 mmole) and allowed to warm up to room temperature, then poured into well stirred ice-water (30 mL). The aqueous solution is then extracted with ethyl acetate (2×30 mL). The combined organic solution is washed with brine (3×30 mL), dried over Na2SO4 and concentrated. The crude product is purified on a silica gel column, gradient eluting with 0-20% ethyl acetate in hexane and concentrated to provide the titled compound as yellow crystalline.

Herkunft & Nachweise