Picric Acid → 2,4,6-Trinitroaniline

HRID 1828379Notes

Reaction equation

HRID 1828379 reaction equation
[C:1]1([C:15](O)=[C:11]([N+:12]([O-:14])=[O:13])[CH:10]=[C:6]([N+:7]([O-:9])=[O:8])[CH:5]=1)[N+:2]([O-:4])=[O:3].C1(C([O-])=C([N+]([O-])=O)C=C([N+]([O-])=O)C=1)[N+:18]([O-])=O.[NH4+].S1(CCCC1)(=O)=O.CN1CCCC1=O>O>[CH:5]1[C:1]([N+:2]([O-:4])=[O:3])=[C:15]([NH2:18])[C:11]([N+:12]([O-:14])=[O:13])=[CH:10][C:6]=1[N+:7]([O-:9])=[O:8]

Participants

6

Reactant 4

HCID 6954Picric AcidHCID 8577Ammonium PicrateHCID 13387N-methyl-2-pyrrolidoneHCID 31347Sulfolane

Product 1

HCID 102712,4,6-Trinitroaniline

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

Replacement of urea with an ammonium salt (or “NH3 reagent”) obtained from ammonia and weak acids (e.g., acetic, carbonic acid, phosphoric acid) produces picramide free of cyanuric acid. Thus, reaction of picric acid or ammonium picrate with an ammonium salt in dipolar aprotic solvents such as sulfolane or N-methylpyrrolidinone (NMP) for several hours at 175–185° C., followed by a water wash, produces picramide that is free of cyanuric acid and ammonium salts. Ammonium hydroxide (28% NH3 in H2O) is unsatisfactory for use as an NH3 reagent as picric acid/ammonium picrate are decomposed to black solids when exposed to the ammonium hydroxide. Example 2 and Table 1 list conversions of 0.18–0.92 g of ammonium picrate in sulfolane to picramide in 8 ml glass pressure tubes.

Workup

  1. washwash

Sources & evidence

ORD record
ord-310ec31297404ffe913e7dd4f01bb353
Source dataset
uspto-grants-2006_06
Patent number
US07057072B2

Reaction notes

Loading…