Reaction #3636

Reaction equation

5,10-dihydro-5-(4-nitrobenzoyl)-4H-pyrazolo-[5,1-c][1,4]benzodiazepine

hydrazine

→

desired product

5,10-Dihydro-5-(4-aminobenzoyl)-4H-pyrazolo-[5,1-c][1,4]benzodiazepine

Solvents

ethyl alcohol

Conditions

Workup

1. 1
   TemperatureThe mixture is heated
2. 2
   Temperatureunder reflux for 3 hours
3. 3
   Filtrationthe mixture is filtered through diatomaceous earth
4. 4
   ConcentrationThe filtrate is concentrated in vacuo to a residue which
5. 5
   workup.DISSOLUTIONis dissolved in methylene chloride
6. 6
   ConcentrationThe filtrate is concentrated in vacuo

Procedure

To a solution of 5 mmol of 5,10-dihydro-5-(4-nitrobenzoyl)-4H-pyrazolo-[5,1-c][1,4]benzodiazepine in 25 ml of ethyl alcohol is added 0.3 g of 10% Pd/C and 15 mmol of hydrazine. The mixture is heated under reflux for 3 hours, and the mixture is filtered through diatomaceous earth. The filtrate is concentrated in vacuo to a residue which is dissolved in methylene chloride and passed through a thin pad of hydrous magnesium silicate. The filtrate is concentrated in vacuo to give the desired product which is purified by flash chromatography on silica gel to give the desired product as a solid, exact mass by mass spectrometry: 305. 1402 (M+H).

Source