Hydrochloric Acid → 6-Methoxy-isoquinoline 2-oxide hydrochloride

Participants

Reaction Steps

At ambient temperature 133 g of m-chloroperbenzoic acid (purity 75%) was added in portions to a stirred solution of 6-methoxy-isoquinoline [Hendricks, J. B. and Rodriguez, C., J. Org. Chem. 1983, 48, 3344-3346; 79.8 g; 500 mmol] in 1.2 L of dichloromethane. Stirring was continued for 3 hours and subsequently methanol (1 L) was added. The bulk was reduced to 700 ml after which 800 ml of a saturated solution of hydrogen chloride in diethyl ether was added. Dilution with 1.5 L of diethyl ether resulted in precipitation of yellow crystals, which were separated by filtration, washed with chilled diethyl ether and dried in vacuo to give 6-methoxy-isoquinoline-N-oxide hydrochloride (85 g, 80%), (+)-FAB-MS 176 [M+H-HCl]+.

Provenance & Evidence