Acetic Acid → 1-(4-methoxybenzyl)-1H-indazole-3-carboximidamide

Participants

Reaction Steps

9.25 g of 1-(4-methoxybenzyl)-1H-indazole-3-carbonitrile (1-1-1, 35.1 mmol, 1 eq.) were suspended in 128 ml of dry methanol under a nitrogen atmosphere. 0.949 g (17.6 mmol, 0.5 eq.) of sodium methanolate were added. The reaction mixture was stirred for 18 hours at room temperature. To the resulting mixture were added 2.82 g (52.7 mmol, 1.5 eq.) of ammonium chloride and 1.0 ml (17.6 mmol, 0.5 eq.) of 100% acetic acid and stirred for 5 hours at 50° C. After cooling down at room temperature the mixture was concentrated in vacuo. The residue was partitioned between aq. half saturated sodium hydrogen carbonate solution and dichloromethane/isopropanol 4:1. The aqueous layer was extracted three times with dichloromethane/isopropanol 4:1. The combined organic layers were washed with brine, dried over magnesium sulfate and concentrated in vacuo. The residue was purified by flash chromatography to yield 6.45 g (23 mmol, 65.5%) of the analytically pure target compound.

Provenance & Evidence