Trimethylsilyl bromide

Trimethylsilyl bromide (TMSBR, also written as (CH3)3SiBr and commonly referred to as bromotrimethylsilane) is an organosilicon reagent with CAS 2857-97-8 and EC 220-672-0. It carries no assigned E-code. It functions as a reactive silylating agent, transferring the trimethylsilyl group to nucleophilic substrates under mild conditions.

In pharmaceutical and biotechnology synthesis, TMSBR cleaves phosphate esters and converts carboxylic acids to their silyl esters, enabling selective protection and deprotection steps. In polymer and coatings formulations, it acts as a crosslinker by reacting with hydroxyl or amine functional groups on polymer backbones, building network density and modifying surface wettability.

TMSBR is supplied as a liquid under REACH registration and handled in accordance with standard organosilane protocols. No Ph.Eur. or FCC monograph applies. It is available in laboratory quantities through to bulk packaging; procurement teams should confirm purity grade and moisture-controlled packaging requirements prior to ordering.