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| | 8-hydrazinylquinoline hydrochloride Basic information |
| | 8-hydrazinylquinoline hydrochloride Chemical Properties |
| Melting point | 63.5-64 °C | | solubility | sol ether, dichloromethane, ethanol. | | form | solid | | color | pale yellow |
| | 8-hydrazinylquinoline hydrochloride Usage And Synthesis |
| Preparation | the original preparation of 8-Hydrazinoquinoline (8-HQ) involved the diazotization of commercially
available 8-aminoquinoline followed by reduction with tin(II) chloride.[1] An improved one-step method has
been developed which starts with the less expensive 8-hydroxyquinoline.[2] Sulfur dioxide (10 g) is
dissolved in hydrazine hydrate (80 mL), 8-hydroxyquinoline (10.16 g) is added and the mixture is refluxed
for 7 d. Every 48 h, EtOH (10 mL) is added to dissolve any starting material which may have sublimed into
the condenser. The mixture is cooled, 2 M NaOH (100 mL) is added, and the resulting emulsion is
extracted with CHCl3 (4 × 75 mL). The combined organic layers are washed with brine (20 mL), dried over
MgSO4, and concentrated. The residue crystallizes upon standing and may be recrystallized from CH2Cl2
and pentane to afford 8.7 g (78%) of 8-HQ as pale yellow needles (eq 1).
 | | storage | 8-hydrazinylquinoline hydrochloride is sensitive to air and light and is best kept under an inert
atmosphere at 0 °C in the dark. Slow decomposition occurs with time and the material turns brown. In the
early stages it can be repurified by recrystallization. Use in a fume hood. | | References | 1. Hünig, S.; Werner, H. LA 1959, 628, 46.
2. Hegde, V.; Hung, C.-Y.; Madhukar, P.; Cunningham, R.; Hpfner, T.; Thummel, R. P. JACS 1993, 115, 872. |
| | 8-hydrazinylquinoline hydrochloride Preparation Products And Raw materials |
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