4-Aminobenzonitrile → 4-Cyanophenylhydrazine Hydrochloride
Reaction equation
[NH2:1][C:2]1[CH:9]=[CH:8][C:5]([C:6]#[N:7])=[CH:4][CH:3]=1.[N:10]([O-])=O.[Na+].O.O.[Sn](Cl)[Cl:17]>Cl.O>[ClH:17].[C:6]([C:5]1[CH:8]=[CH:9][C:2]([NH:1][NH2:10])=[CH:3][CH:4]=1)#[N:7]Participants
Conditions
- Temperature
- -15 °C
Procedure
To a cooled (-15° C.) and stirred suspension of 4-aminobenzonitrile (50 g, 423 mmol) in concentrated hydrochloric acid (550 ml) was added dropwise a solution of sodium nitrite (31.5 g, 457 mmol) in water (200 ml) at such a rate as to maintain the temperature below -10° C. After the addition was finished, the reaction mixture was quickly filtered to remove solids and the filtrate was added portionwise to a cooled (-20° C.) and stirred solution of tin (II) chloride dihydrate (477 g, 2.1 mol) in concentrated hydrochloric acid (370 ml) at such a rate as to maintain the temperature below -10° C. After further 15 minutes at -10° to 0° C., the white precipitate was collected by filtration, washed with diethyl ether (4×250ml) and dried to give 56 g (78%) of the title compound; mp 235°-237° C. (ethanol-water 1:1); 1H NMR (250MHz, D6 -DMSO) δ10.50 (3H, br s, -N+H3) 9.10 (1H, br s, --NH--), 7.71 (2H, d, J=8.8Hz, Ar--H), 7.03 (2H, d, J=8.8Hz, Ar--H); m/z (CI) 132 (M+ -1).
Workup
- temperatureto maintain the temperature below -10° C
- additionAfter the addition
- filtrationthe reaction mixture was quickly filtered
- customto remove solids
- additionthe filtrate was added portionwise to
- temperaturea cooled (-20° C.)
- temperatureto maintain the temperature below -10° C
- filtrationthe white precipitate was collected by filtration
- washwashed with diethyl ether (4×250ml)
- customdried
Sources & evidence
- ORD record
- ord-c8e6409d66cc4322923c18e2871127ce
- Source dataset
- uspto-grants-1996_05
- Patent number
- US05514682
Reaction notes
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