N-bromobutanimide → 1-Bromo-3-(bromomethyl)-5-methylbenzene

Participants

Reaction Steps

A mixture of 3,5-dimethylbromobenzene (70 g, 0.378 M), NBS (67.3 g, 0.373 M), and benzoyl peroxide (2.27 g, 0.009 M) in carbon tetrachloride (300 mL) was refluxed for 3 hr. After cooling to room temperature, the mixture was filtered and the filtrate was evaporated in vacuo to give a pale brown oil. The crude product was dissolved in hexane and filtered through a short silica gel pad (diameter: 9.5 cm, height: 7 cm). The silica gel pad was washed with hexane until the product eluted completely. The filtrate was evaporated in vacuo to give 94 g of 1-bromo-3-(bromomethyl)-5-methylbenzene (contaminated with starting material and 1-bromo-3,5-bis-bromomethylbenzene) as a pale brown oil, which solidified on standing at room temperature. The mixture was used directly in the next reaction without further purification.

Provenance & Evidence