6-Chloropyridazin-3-ol

6-Chloropyridazin-3-ol (CAS 19064-67-6) is a strategically functionalized pyridazine scaffold engineered for agrochemical and pharmaceutical intermediate synthesis. This molecule integrates a pyridazine core—a six-membered heterocycle with two adjacent nitrogen atoms—with a chlorine substituent at the C6 position and a hydroxyl group at the C3 position. The C6-chloro handle is activated by the adjacent ring nitrogens, enabling efficient nucleophilic aromatic substitution (SNAr) or Pd-catalyzed cross-coupling, while the 3-hydroxyl moiety exists in tautomeric equilibrium with the 3-one form (pyridazin-3-one), offering versatile alkylation or derivatization sites. This intermediate is particularly valuable for constructing pyridazinone herbicides, kinase inhibitor cores, and heterocyclic libraries where the adjacent nitrogen pattern provides unique hydrogen-bonding geometry and electronic properties compared to pyridine or pyrimidine analogs. Manufactured under controlled conditions, it supports drug discovery and agrochemical development programs requiring modular access to chlorinated diazine architectures.

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Product Name	6-Chloropyridazin-3-ol
CAS Number	19064-67-6
Chinese Name	6-氯哒嗪 -3-醇
Synonyms	6-Chloro-3-hydroxypyridazine; 6-Chloropyridazin-3(2H)-one; C₄H₃ClN₂O heterocycle; Chlorohydroxypyridazine
Chinese Synonyms	6-氯 -3-羟基哒嗪; 6-氯哒嗪 -3-酮; 氯羟基哒嗪; 6-氯 -3-氧代哒嗪
Molecular Formula	C₄H₃ClN₂O
Molecular Weight	130.53 g/mol
Purity	≥ 98% (HPLC area normalization)
Product Category	Pharmaceutical Intermediates / Agrochemical Intermediates / Pyridazine Derivatives
Appearance	Off-white to Light Yellow Crystalline Powder
Melting Point	~230-235°C (decomposition, literature reference recommended)
Storage Conditions	Store in a cool, dry, well-ventilated area away from light and moisture. Keep container tightly closed. Protect from strong bases to avoid hydrolysis of the C6-Cl bond or ring degradation.
Shelf Life	24 months under recommended storage conditions
Packaging	100g/bottle, 500g/bottle, 1kg/bottle, 5kg/drum, or customized according to customer requirements
Applications	Pyridazinone herbicide synthesis, kinase inhibitor scaffold development, heterocyclic library construction, nucleophilic substitution at C6, O-alkylation at C3
Reactivity	Suitable for nucleophilic aromatic substitution (C6-Cl displacement), O-alkylation/acylation (C3-OH), Pd-catalyzed cross-coupling, tautomerization control, and ring fusion reactions
Special Note	✅ Tautomeric Scaffold—exists as 3-ol/3-one equilibrium. C6-Cl is highly activated by adjacent nitrogens for substitution. Distinct from pyridine/pyrimidine by N-N adjacency. Part of our diazine building block series.