Boron tribromide → 6-hydroxy-1-(5-isopropyl-1H-indazol-4-yl)-3-methyl-isoquinoline-4-carbaldehyde

Beteiligte Stoffe

Reaktionsschritte

BBr3 (8.8 g, 35 mmol) is added slowly to a solution of 1-(5-Isopropyl-1H-indazol-4-yl)-6-methoxy-3-methyl-isoquinoline-4-carbaldehyde (842 mg, 2.3 mmol) in DCM (15 ml) at −78° C. The cold bath is removed and the mixture is warmed to room temperature, and then stirred for a further 1 h. The reaction mixture is poured into ice-water mixture and treated with NH4OH (6 ml). The layers are separated and the aqueous layer is extracted with DCM. The combined organic layers are dried (Na2SO4) and evaporated. The residue is chromatographed on silica gel eluting with EtOAc/MeOH (20:1) to give 490 mg of starting material and 276 mg of 6-hydroxy-1-(5-isopropyl-1H-indazol-4-yl)-3-methyl-isoquinoline-4-carbaldehyde. 1H NMR (CDCl3) 10.9 (s, 1H), 8.87 (s, 1H), 7.62-7.42 (m, 4H), 6.99 (d, 1H), 3.09 (s, 3H), 2.73-2.67 (m, 1H), 1.23 (d, 3H), 1.12 (d, 3H).

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