1,3-Dibromo-5,5-dimethylhydantoin

Introduction

Aromatic bromination with elemental bromine is one of the most widely used and extensively studied reagents. [1] Owing to low reactivity, high toxicity, and handling inconvenience, some alternative brominating agents have been developed. However, a stable, solid reagent is always preferred, particularly for small-scale reactions that require a specific amount of brominating reagent. On the other hand, getting regioselective monobromination is also important, because it is very common to obtain a ­mixture of monobromides and dibromides. [2] The com­mercially available 1,3-dibromo-5,5-dimethylhydantion ­(DBDMH) meets most of the requirements mentioned. It is an excellent reagent for the bromination of aromatic rings, particularly for phenols and polyphenols. It gives excellent yields with a variety of aromatic rings including ­protected and unprotected phenol and polyphenol derivatives, and those that contain carboxylic acids. The reaction is usually faster and the conditions are mild (at or below room temperature). In addition to the bromination activity, we found it to be an excellent oxidant for the oxidation of thiols to disulfides in extremely high yield.

References

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