Dimethylformamide → Isoquinoline-4-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

n-Butyllithium (1.6 M in hexanes, 11.0 ml, 17.6 mmol) is added dropwise to a stirred solution of 4-bromoisoquinoline (3.02 g, 14.5 mmol) and anhydrous tetrahydrofuran (100 ml) at −78° C. under nitrogen. The reaction is stirred for 45 min at −78° C. and then dimethylformamide (6.0 ml, 77.5 mmol) is added. The reaction is then stirred for 3 h at −78° C. before it is quenched with water. The reaction is then poured into saturated sodium bicarbonate solution (200 ml) and extracted with ethyl acetate (100 ml×3). The ethyl acetate is washed with brine and dried over sodium sulfate. The sodium sulfate is filtered and the crude product is concentrated on a rotary evaporator. The crude product is purified by flash chromatography on silica gel eluting with 50% ethyl acetate/hexanes to yield (0.74 g, 33%) of isoquinoline-4-carboxaldehyde: mass spectrum (ion spray): m/z=158.1 (M+1).

Provenance & Evidence