Diisobutylaluminum hydride → Isoquinoline-3-carboxaldehyde

Participants

Reaction Conditions

Reaction Steps

To a cooled solution 0° C. of isoquinoline-3-carboxylic acid methyl ester (1.0 g, 5.34 mmol) in anhydrous tetrahydrofuran (100 ml), is added a solution of DIBAL-H (11.8 ml, 11.8 mmol). The reaction mixture is stirred at 0° C. for 2 hours and then quenched with saturated aqueous sodium potassium tartrate and stirred for 2 hours. The layers are separated and the aqueous layer is extracted with ethyl acetate. The combined organic extracts are washed with 1N HCl, 2N NaOH, and dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The crude reaction mixture is purified on silica gel eluting with 20% ethyl acetate/hexanes to give isoquinoline-3-carboxaldehyde (0.46 g, 54%). 1H NMR (CDCl3): δ=10.24 (1H, brs), 9.32 (1H, brs), 8.35 (1H, brs), 8.02 (2H, brd), 7.77 (2H, brs).

Provenance & Evidence