Sodium Carbonate → HCID 20040881, compound
Reaction equation
[NH2:1][C:2]1[C:6]2=[N:7][C:8]([CH3:12])=[CH:9][C:10]([Cl:11])=[C:5]2[NH:4][N:3]=1.[N:13]([O-])=O.[Na+].C(=O)([O-])[O-].[Na+].[Na+]>O.S(=O)(=O)(O)O>[Cl:11][C:10]1[CH:9]=[C:8]([CH3:12])[N:7]=[C:6]2[C:2](=[N+:1]=[N-:13])[N:3]=[N:4][C:5]=12Participants
Procedure
A solution of 3-amino-7-chloro-5-methyl-1H-pyrazolo[4,3-b]pyridine (D7) (0.5 g) in water (13.5 ml) and concentrated sulphuric acid (2 ml) was treated at 0° with a solution of sodium nitrite (0.406 g) in water (2 ml) added dropwise with stirring. On completion of the addition the mixture was stirred at 0° for 20 min before bringing to pH 8 with saturated sodium carbonate. The resulting solid was collected and dried (0.18 g). The filtrate was extracted with chloroform (3×50 ml), the combined extracts dried with magnesium sulphate, filtered and evaporated to dryness to give a yellow solid which was combined with the solid originally collected, m.p. 119°-124° (combined yield 0.5 g). This crude material was recrystallised from cyclohexane to give the title compound as yellow needles (0.358 g, 68%), m.p. 123.5°-125° (decomposition). (Found: C, 43.51; H, 1.88; N, 35.79; Cl, 18.68. C7H4ClN5 requires C, 43.43; H, 2.08; N, 36.17; Cl, 18.31%). Found M+ 193.0154, C7H4ClN5 requires 193.0155.
Workup
- additionadded dropwise
- additionOn completion of the addition the mixture
- stirringwas stirred at 0° for 20 min
- customThe resulting solid was collected
- customdried (0.18 g)
- extractionThe filtrate was extracted with chloroform (3×50 ml)
- dry with materialthe combined extracts dried with magnesium sulphate
- filtrationfiltered
- customevaporated to dryness
- customto give a yellow solid which
- customoriginally collected
- customThis crude material was recrystallised from cyclohexane
Sources & evidence
- ORD record
- ord-37daccc0d9f44a7bb384b1b54cec1c73
- Source dataset
- uspto-grants-1989_05
- Patent number
- US04833136
Reaction notes
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