Benzoyl Hydrazine丨CAS 613-94-5

Benzoyl hydrazine is a versatile small-molecule building block used across organic synthesis, medicinal chemistry, and materials research. It is commonly employed as a reagent for constructing hydrazones, semicarbazones and related imine-type linkages (via condensation with carbonyls), which are useful in the preparation of drug candidates, molecular probes and linkers for bioconjugation. In heterocycle synthesis it serves as a precursor for pyrazoles, isoxazoles and other nitrogen-rich rings by cyclization reactions. The compound is also used in coordination chemistry to prepare metal–hydrazide complexes and as an intermediate in the synthesis of agrochemicals, dyes and specialty fine chemicals where the hydrazide motif is required.

Benzoyl hydrazine offers high chemical reactivity and selectivity: the hydrazide NH–NH fragment readily forms stable hydrazones under mild conditions, enabling straightforward and high-yielding transformations with aldehydes and ketones. Its benzoyl cap moderates reactivity relative to unsubstituted hydrazine, improving handling and reducing side reactions while still permitting downstream modifications (acylation, alkylation, cyclization, reductions). The compound's compatibility with common solvents and catalysts, and its amenability to both solution- and solid-phase chemistry, make it convenient for parallel synthesis and library generation. Additionally, hydrazone and pyrazole derivatives derived from benzoyl hydrazine often display useful biological activities, so the reagent is valuable for rapid SAR exploration.