Chemical Structure and Molecular Features

4-(2H-Benzo[d][1,2,3]triazol-2-yl)benzene-1,3-diol belongs to the class of 2-aryl-2H-benzotriazoles, a well-established family of UV-absorbing heterocycles. Its structure consists of a benzotriazole bicyclic ring system connected at the triazole N-2 nitrogen to a phenyl ring that bears hydroxyl substituents at the 1- and 3-positions (i.e., a resorcinol unit). The N-2 substitution pattern is characteristic of 2H-tautomers in the benzotriazole series, which are generally more stable than the corresponding 1H-isomers in N-aryl derivatives.

The two phenolic hydroxyl groups of the resorcinol moiety confer significant hydrogen-bonding capacity and tune the electron density of the pendant aryl ring. Together with the electron-deficient benzotriazole chromophore, this push–pull electronic arrangement is responsible for strong intramolecular charge-transfer character and consequent broad UV absorption. The planar, conjugated architecture of the molecule further supports its photophysical behavior.

Physicochemical Properties

As a solid aromatic compound, 4-(2H-Benzo[d][1,2,3]triazol-2-yl)benzene-1,3-diol is expected to exhibit moderate to high melting point typical of planar, hydrogen-bonded crystalline organic molecules. The presence of two hydroxyl groups allows intermolecular hydrogen bonding in the solid state, contributing to crystal lattice stability.

Solubility behavior is governed by the dual hydrophilic (hydroxyl groups) and hydrophobic (aromatic rings) character of the molecule. It is expected to show limited solubility in water but improved solubility in polar organic solvents such as ethanol, dimethyl sulfoxide (DMSO), and acetone. The phenolic OH groups may also confer mild acidity, with pKa values typical of substituted phenols.

The UV absorption profile is a defining physicochemical property. Hydroxyphenyl benzotriazoles characteristically absorb in the 300–385 nm range (UVA/UVB), making them effective photostabilizer candidates. Exact spectroscopic data for this specific compound should be verified against experimental measurements.

Research Applications

UV Absorption and Photostabilization Research: Hydroxyphenyl benzotriazole derivatives are among the most extensively studied classes of organic UV absorbers. 4-(2H-Benzo[d][1,2,3]triazol-2-yl)benzene-1,3-diol, bearing the resorcinol motif, is of interest for fundamental photophysical studies and as a model compound to understand structure–property relationships governing UV absorption efficiency and photostability.

Heterocyclic and Synthetic Chemistry: The compound serves as a versatile building block or reference standard in the synthesis of more complex benzotriazole-containing molecules. Its dual hydroxyl groups provide handles for further functionalization via etherification, esterification, or coordination chemistry with metal ions.

Materials Science: Benzotriazole UV absorbers are incorporated into polymer matrices, coatings, and films to prevent photodegradation. Research-grade compounds such as this one are used to benchmark performance, develop structure–activity models, and validate analytical methods such as HPLC and UV-Vis spectroscopy in quality-control contexts.

Coordination Chemistry: The combination of the nitrogen-rich triazole ring and phenolic hydroxyl groups makes this compound a potential ligand for metal complexation studies, relevant to catalysis and materials research.

Handling, Storage, and Safety Considerations

As with all aromatic phenolic compounds, standard laboratory safety precautions should be observed when handling 4-(2H-Benzo[d][1,2,3]triazol-2-yl)benzene-1,3-diol. Researchers should consult the Safety Data Sheet (SDS) provided by Aladdin Scientific before use. Personal protective equipment including gloves, safety glasses, and a laboratory coat is recommended.

The compound should be stored in a cool, dry, well-ventilated location, away from strong oxidizing agents and direct light exposure. Sealing the container tightly after use helps to prevent moisture uptake and potential degradation. Specific storage temperature recommendations, exact hazard classifications, and GHS pictograms should be verified from the product SDS.

Waste disposal must comply with applicable local, regional, and national environmental regulations governing aromatic and nitrogen-heterocyclic compound disposal.

Product Specification and Ordering Information

Aladdin Scientific offers 4-(2H-Benzo[d][1,2,3]triazol-2-yl)benzene-1,3-diol under SKU B725491. Researchers and procurement teams are encouraged to contact Aladdin Scientific for current purity specifications, available pack sizes, pricing, and lead times. Bulk quantities and custom specifications may be available upon request.

For accurate molecular weight, exact purity grade, analytical data (NMR, HPLC), and Certificate of Analysis (CoA), please refer to the official product page or contact Aladdin Scientific customer support directly.