The question is to make Sec-butyl Bromide from alcohol. From what i have read, 2° and 3° alkyl bromide and alkyl iodide cannot be formed with Conc H2SO4 as it will make it into alkene.

I have tried P4 + 6Br2 = 4PBr3 But-2-ol + PBr3 = 3 2-bromo butane + H3PO3

Is there any other way?


1 Answer 1


A good way is to form a sulfonate of the alcohol (tosylate, mesylate, triflate etc) forming a good leaving group then react that with a source of bromide anion.

The standard way of forming a tosylate is with p-toluenesulfonyl chloride in the presence of a base, pyridine catalyses the reaction so is often used as the base. There are many ways to react the tosylate with a source of bromide. I prefer using phase-transfer catalysis in dichloromethane/aqeous potassium bromide with tetrabutylammonium bromide catalysis, this works for mesylates too.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.