Pyrazole Structure Properties Synthesis and Uses

Technical Specifications & Chemical Properties

We supply high-purity Pyrazole (CAS 288-13-1) engineered to meet strict international standards for pharmaceutical and agrochemical synthesis. Our high-grade 1H-Pyrazole ensures low impurity profiles, excellent batch consistency, and reliable reactivity across all downstream processing applications.

Product Identification Overview

Parameter	Specification / Property
Chemical Name	Pyrazole (1,2-Diazole)
CAS Registry Number	288-13-1
Molecular Formula	C3H4N2
Molecular Weight	68.08 g/mol
Assay (GC)	≥ 99.0%
Appearance	White to off-white crystalline solid
Melting Point	67 – 70 °C
Boiling Point	186 – 188 °C
Solubility	Freely soluble in water, ethanol, ether, and chloroform

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Structural & Chemical Characteristics

Pyrazole is a key aromatic heterocyclic building block featuring two adjacent nitrogen atoms in a planar 5-membered ring. Its unique electronic structure offers distinct reactivity patterns essential for fine chemical synthesis:

• Prototropic Tautomeric Equilibrium: Unsubstituted 1H-Pyrazole exhibits rapid interconversion between tautomeric forms in solution, making the 3- and 5-positions chemically equivalent.
• Controlled Basicity: With a pKa of 2.48, it acts as a weak base and a versatile N-donor ligand, balancing chemical stability with high synthetic utility.
• C-4 Functionalization: High electron density drives regioselective electrophilic aromatic substitution primarily at the C-4 position for efficient halogenation, nitration, and formylation.
• N-Alkylation Capabilities: The NH center undergoes smooth N-alkylation, acylation, and arylation, serving as an ideal platform for developing complex active pharmaceutical ingredients (APIs) and crop protection compounds.

Key Industrial Applications & Synthetic Utility

Pharmaceutical Intermediates & API Synthesis

As a core heterocyclic building block, pyrazole plays a critical role in modern drug discovery and commercial scale-up. We supply high-purity 1H-pyrazole engineered to meet strict chemical specifications for pharmaceutical intermediates and API synthesis.

• NSAID Production: Serves as the key structural core for selective COX-2 inhibitors, including Celecoxib.
• Targeted Cancer Therapies: Precursor in the synthesis of specialized small-molecule kinase inhibitors and anti-cancer compounds.
• Enzyme Inhibition: Acts as the functional foundation for alcohol dehydrogenase (ADH) inhibitors like Fomepizole.

Agrochemical & Crop Protection Formulations

Our pyrazole is widely utilized across the agrochemical sector to produce targeted, highly effective agrochemical active ingredients. Its ring structure offers excellent metabolic persistence and environmental stability in crop protection products.

Application Category	Downstream Agrochemical Uses	Key Functional Value
SDHI Fungicides	SDHI fungicide intermediates (e.g., Fluxapyroxad, Bixafen)	Broad-spectrum fungal pathogen control
Insecticides	Pyrazole carboxamide insecticides (e.g., Chlorantraniliprole derivatives)	High target specificity and reduced field dosage rates

Coordination Chemistry & Material Science

In material science, pyrazole functions as a versatile bifunctional ligand featuring two adjacent nitrogen donor atoms. We deliver consistent, high-assay batches designed for advanced synthesis:

• Metal-Organic Frameworks (MOFs): Excellent coordinating linkers for constructing thermally stable porous MOFs and supramolecular networks.
• Homogeneous Catalysis: Reliable chelating ligands for transition-metal catalysts used in complex industrial cross-coupling reactions.

Synthetic Routes & Green Chemistry Manufacturing

We manufacture high-purity pyrazole using optimized chemical pathways that balance high batch yields with strict environmental standards. Our scalable facility processes ensure reliable chemical consistency whether you need standard commercial volumes or custom purity grades.

Classic Commercial Synthesis

Our primary industrial production leverages the condensation of 1,3-dicarbonyl compounds with hydrazine derivatives. This proven synthetic route allows us to efficiently construct the core 1,2-diazole ring structure on a bulk scale.

• High Conversion Efficiency: Direct condensation minimizes unreacted starting materials and side reactions.
• Automated Thermal Control: Computer-controlled reaction parameters manage exothermic steps safely, ensuring consistent batch-to-batch output.
• Reliable Supply Base: Produces a high-assay heterocyclic building block ready for immediate industrial use or downstream processing.

Sustainable Green Process Innovations

To align with modern ESG guidelines and global regulatory demands, we have integrated green engineering practices directly into our 1H-pyrazole manufacturing lines.

Innovation Focus	Process Modification	Buyer Advantage
Low-Waste Catalysis	Atom-economical catalytic pathways	Reduces solvent consumption and overall chemical waste
Byproduct Reduction	Elimination of halogenated reaction media	Yields cleaner chemical streams with lower trace impurity levels
Particle Size Control	Precision-controlled crystallization	Delivers consistent powder flowability and reliable dissolution rates

Our advanced crystallization protocols give you tight control over particle size distribution, preventing caking and simplifying bulk handling in automated production environments.

Quality Control & Compliance for Pyrazole

Analytical Quality Assurance

We enforce strict testing protocols on every batch of pyrazole to guarantee high purity, batch-to-batch reproducibility, and reliable chemical performance. Our in-house quality control laboratory evaluates all lots prior to release using advanced analytical methods:

• Gas Chromatography (GC): Verifies assay purity levels at >= 99.0% while profiling and limiting trace impurities.
• Proton NMR (1H-NMR): Confirms structural identity and verifies tautomeric purity.
• Karl Fischer Titration: Controls water content strictly to meet low moisture thresholds required for sensitive organic syntheses.
• Third-Party Verification: We partner with independent accredited testing agencies, including SGS and Bureau Veritas, for certified third-party analysis upon request.

Regulatory Documentation & Global Compliance

We streamline your procurement and compliance processes by delivering complete documentation with every shipment. Our production facilities operate under ISO 9001 certified quality management standards to ensure total batch traceability.

Quality Parameter	Verification Method	Documentation Provided
Purity Assay	In-house GC (>= 99.0%)	Batch Certificate of Analysis (COA)
Structure Identity	1H-NMR Spectroscopy	Technical Data Sheet (TDS)
Moisture Limit	Karl Fischer Titration	Batch Inspection Report
Safety Data	GHS Revision 8 Standards	Material Safety Data Sheet (MSDS) / SDS
Plant Standard	ISO 9001 Quality Audit	ISO Certificate & REACH Support

• Batch COA: Issued with every shipment, displaying exact lot-specific test results for purity, melting point, and water content.
• GHS Revision 8 SDS: Up-to-date Material Safety Data Sheet (MSDS) and Technical Data Sheets aligned with international safety regulations.
• REACH Registration Support: Regulatory support and documentation available for seamless import into the European market and other global jurisdictions.

Packaging, Safe Handling & Global Logistics

We prioritize product purity, worker safety, and seamless international transport. Pyrazole (CAS 288-13-1) requires strict environmental controls during handling and shipping to maintain its chemical integrity and meet all global regulatory standards.

Storage & Hazard Guidelines

• Inert Gas Storage: We package and store pyrazole under an inert nitrogen environment to prevent moisture absorption and atmospheric degradation. Drums must remain tightly sealed in a cool, dry, and well-ventilated area away from direct heat and strong oxidizing agents.
• GHS Hazard Classifications: Pyrazole is classified as harmful if swallowed (Acute Toxicity Category 4), causes skin irritation (Category 2), causes serious eye damage (Category 1), and may cause respiratory irritation (STOT SE 3). Always review our GHS Revision 8 Material Safety Data Sheet (MSDS/SDS) prior to processing.
• Recommended PPE Protocols:
• Eyes & Face: Chemical splash goggles or full-face protective shields.
• Skin Protection: Heavy-duty nitrile gloves and chemical-resistant coveralls.
• Respiratory Safety: NIOSH-approved dust and organic vapor respirators when opening or transferring bulk containers.

Flexible Packaging & Global Export

Package Size	Container Specification	Best For
1 kg Sample Bags	Multi-layer vacuum-sealed aluminum foil bags with desiccant	Lab evaluations, R&D trials, and custom pilot testing
25 kg Fiber Drums	UN-certified heavy-duty fiber drums with double PE inner liners	Large-scale commercial production and industrial sourcing

• International Shipping Compliance: As a reliable bulk fine chemical supplier, our freight logistics strictly comply with IMDG (sea), ICAO/IATA (air), and ADR (land) transport codes.
• Complete Customs Clearance Documentation: Every export consignment includes a batch-specific Certificate of Analysis (COA), REACH compliance statements, safety data sheets, and official commercial invoices for smooth global customs entry.

Direct Pyrazole Manufacturer Advantages

Sourcing Pyrazole directly from our manufacturing facilities eliminates third-party trading markups, stabilizes your raw material supply chain, and guarantees high batch-to-batch consistency for your synthetic workflows. We maintain a reliable, year-round inventory of CAS 288-13-1 to fulfill both small-scale pilot needs and large industrial bulk orders without dispatch delays.

Procurement Aspect	Our Direct Factory Supply	Intermediate Trading Brokers
Pricing Structure	Factory-direct rates with zero middleman markups	Added 15%–30% distributor margins
Stock Availability	Stable year-round inventory reserved for contract buyers	Unpredictable stockouts and variable lead times
Batch Consistency	Strict QA protocols ensuring consistent reaction yields	Mixed sourcing risks and variable purity levels
Technical Support	Direct access to synthesis chemists and lab documentation	Limited or delayed technical responsiveness

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Streamlined RFQ & Bulk Pyrazole Procurement Process

We keep our bulk ordering process fast, direct, and transparent to ensure your production schedules run without interruption.

• Submit Your RFQ: Send us your volume requirements, target purity grades, and any custom particle size or packaging requests.
• Guaranteed 24-Hour Quotation: Receive a comprehensive quote within 24 hours, detailing direct unit pricing, tiered bulk discounts, and shipping terms.
• Custom Specifications & Sample Testing: Request tailored packaging options (from 1 kg trial bags to 25 kg fiber drums) along with pre-shipment evaluation samples.
• Order Fulfillment & Tracking: Every batch ships with an aligned Certificate of Analysis (COA) and complete regulatory documentation for smooth customs clearance.

Frequently Asked Questions About Pyrazole

1H-Pyrazole vs. 3H-Pyrazole Tautomeric Differences

In organic synthesis, pyrazole acts as a tautomeric heterocycle. The 1H-pyrazole tautomer dominates standard reaction conditions because it maintains a fully aromatic structure. The 3H-pyrazole form is non-aromatic and exists only as a transient, reactive intermediate unless specific substituents lock the double bonds.

Feature	1H-Pyrazole	3H-Pyrazole
Aromaticity	Fully aromatic (6 pi-electron system)	Non-aromatic
Stability	Thermodynamically stable, primary form	Transient intermediate
Application	Standard heterocyclic building block	Specific rearrangement reactions

Bulk Handling, Storage, and Safety Guidelines

Proper safety protocols are essential when handling bulk pyrazole (CAS 288-13-1) in manufacturing facilities:

• Personal Protective Equipment (PPE): Use safety goggles, nitrile gloves, protective clothing, and a NIOSH-approved dust respirator.
• Storage Environment: Store in a cool, dry, well-ventilated warehouse under an inert gas blanket (nitrogen) to prevent moisture pickup.
• Chemical Incompatibilities: Keep separated from strong oxidizing agents, strong acids, and ignition sources.

Ordering Samples, Custom Grades, and Documentation

As a direct bulk fine chemical supplier, we simplify your raw material procurement with direct factory support:

• Custom Purity Grades: We deliver standard >= 99.0% assay material alongside tailored purity specifications for specific reaction pipelines.
• Sample Orders: Request 1 kg evaluation samples shipped in sealed aluminum foil bags for immediate lab validation.
• Regulatory Docs: Access batch-specific Certificate of Analysis (COA) and Material Safety Data Sheet (MSDS) files through our 24-hour response team.