Reaction #42905

Reaction equation

1-(1,3-dioxo-1,3-dihydro-isoindol-2-ylmethyl)-6,8-dimethoxy-isoquinoline-4-carboxylic acid ethyl ester

ethanol hydrazine monohydrate

→

1-aminomethyl-6,8-dimethoxy-isoquinoline-4-carboxylic acid ethyl ester

Yield 123.5%

Conditions

Workup

1. 1
   Temperaturethe reaction was cooled to room temperature
2. 2
   Otherthe phthalhydrazide precipitate was removed by filtration
3. 3
   Washrinsing with ethanol
4. 4
   ConcentrationThe filtrate was concentrated under reduced pressure

Procedure

To a solution of 1-(1,3-dioxo-1,3-dihydro-isoindol-2-ylmethyl)-6,8-dimethoxy-isoquinoline-4-carboxylic acid ethyl ester (1.22 g, 2.90 mmol) in 80 mL of absolute ethanol hydrazine monohydrate (1.59 g, 31.8 mmol) was added and the mixture was stirred under a nitrogen atmosphere at 40° C. After 4 h, the reaction was cooled to room temperature, and the phthalhydrazide precipitate was removed by filtration, rinsing with ethanol. The filtrate was concentrated under reduced pressure to give 1.04 g of crude 1-aminomethyl-6,8-dimethoxy-isoquinoline-4-carboxylic acid ethyl ester, which was used directly the next step. H1-NMR (DMSO): δ, 8.84 (s, 1H), 7.81 (d, 1, J=2.4 Hz), 6.76 (d, 1H, J=2.3 Hz), 4.36 (q, 2H, J=7.13), 4.32 (s, 2H), 3.95 and 3.88 (s, 3H each), 1.35 (t, 3H, J=7.2 Hz); MS: APCI (M+H) calc'd for C15H18N2O4+H 291.3; found 291.1.

Source