High purity 2,4-Dihydroxybenzoic Acid

High purity 2,4-Dihydroxybenzoic acid is a white to cream or pale pink crystalline powder in the form of needles; it may turn slightly pink upon prolonged exposure to air or light. It has a faint phenolic odor and a slightly bitter taste. It is soluble in hot water, ethanol, diethyl ether, acetone, and ethyl acetate, and dissolves readily in alkaline aqueous solutions by forming salts. It exhibits the dual reactivity characteristics of both salicylic acid (an *ortho*-hydroxybenzoic acid) and resorcinol (a 1,3-dihydroxybenzene).

Send Inquiry

Product Introduction

Zouping Jinxing Chemical Co., Ltd. is one of the leading manufacturers and suppliers of High purity 2,4-Dihydroxybenzoic Acid in China. If you're going to wholesale bulk High purity 2,4-Dihydroxybenzoic Acid made in China, welcome to get free sample from our factory. All customized products are with high quality and low price.

Basic physical properties

High purity 2,4-Dihydroxybenzoic Acid:

Appearance: White needle-like crystals (crystallizes with water from aqueous solution; converts to anhydrous form at 100 °C); turns slightly pink upon prolonged storage or exposure to light.
Melting point: 208–211 °C (decomposition); ~213 °C with rapid heating; anhydrous form can reach 218–219 °C with slow heating.
Boiling point: ~237 °C (rough estimate); difficult to distill at atmospheric pressure due to concurrent decomposition.
Density: ~1.37 g/cm³ (estimated); experimentally measured value ~1.56 g/cm³.
Solubility: Water 8 g/L (20 °C); soluble in hot water, ethanol, diethyl ether, acetone, and ethyl acetate; readily soluble in alkaline aqueous solutions (forming salts); LogP ≈ 0.98 (pH 3.5).
pKa: 3.11 (COOH), 8.55 (phenolic OH), ~14 (second phenolic OH) at 25 °C.
UV/FeCl₃: Produces a red color with ferric chloride (characteristic of *ortho*-phenolic hydroxyl groups); commonly used for identification.
Flash point: ~200 °C; combustible solid; not classified as highly flammable or explosive.

Primary Uses

Pharmaceutical intermediates: Synthesis of mycophenolic acid, PDE4 inhibitors, HSP90 inhibitors, hydroxylated xanthenes, etc.
Dyes/Coupling components: Azo dye intermediate (Coupler 320)
Analytical reagents: Spot test for Fe³⁺ (color reaction), colorimetric determination of Ti, etc.; MALDI-MS matrix (polymer)
Food flavoring: FEMA 3798, GRAS; trace antioxidant flavoring for cold drinks, beverages, and desserts (cold drink grade: 450 mg/kg)
Plant/Metabolite: Naturally occurring in potatoes and coconuts; human urinary metabolite

Safety and Physiology

Toxicity of High purity 2,4-Dihydroxybenzoic Acid: Low toxicity. Intraperitoneal LD₅₀ in mice >800 mg/kg; low oral risk in rats; irritating to skin, eyes, and respiratory tract (R36/37/38).
GHS: Xi (Irritant); standard protective measures (e.g., P261/P264/P280).
Storage and Transport: Store in a sealed container, protected from light, at room temperature (<30°C) or in a cool, dry place; keep separate from strong oxidizers; not classified as hazardous for transport (NONH).