I tried this once with disasterous results. At first I used amounts of everything as I had calculated above, but not all the KBr reacted so I ended up using a 50% excess of sulfuric acid and H2O2, sulfuric acid worked better than HCl for some reason. So first I mixed the sulfuric acid with the KBr. That way it wouldn't be too acidic when I added the iso. Would sulfuric hurt iso? Then I mixed in the DCM and the iso. I let this stir for a while and it turned yellow. Then I started to drip in h2o2(15%) but there was no color change when it hit, so I just threw it all in. It took a couple minuites to turn orange. I had the worst time making sure it had all reacted. I would let it stir for an hour in the future. I played with it for the longest time, washed the water 3X with DCM, added all the DCM/dibromoiso together and weighed. It was rediculously underweight, but I had played with the liquids so much that I could have lost a lot. Anyway I decided to distill out the DCM. I setup to distill and forgot about it. OOPS!!! When I came back the room was so thick with bromine gas that I couldn't see, breath, etc. I put on my gas mask, and proceded to the setup. I turned off the hotplate. And pulled out the stoppers. A LOT of gas escaped and It was presurized. ALL the glass had filled up with a tar. Once it cooled it had the consistancy and color of charcoal. The volume of the stuff must have increased 10 times at least. It was rediculous. The stuff was rock hard. I tried cleaning it with everything. HCl did nothing, DCM, toluene, and acetone did nothing. Sulfuric reacted a little and loosened it enough so that air could go in one end and out the other and finally methanol dissolved it a little. I setup for reflux with methanol and that cleaned out half the condensor. I guess I'll distill a whole lot of methanol. Anyway what happened? I thought it would come over in the order of DCM/Br2?/dibromoisosafrole. Insted the dibromostuff must have broken down. Or was something else wrong. I want to try this again.