[Dynamo22]

I'm still a little confused I guess. I can see how a hoffman would produce the alkene (my book uses Ag2O not NaOH). I guess I'm confused how the ring would form in product B from product A. Would the initial amine formed attack the bromine on the end opposite of it to form the ring? The hint also talks about a charged species in product A, that is also throwing me off. Would the Nitrogen be the charged atom?

[orgopete]

I'm still a little confused I guess. I can see how a hoffman would produce the alkene (my book uses Ag2O not NaOH). I guess I'm confused how the ring would form in product B from product A. Would the initial amine formed attack the bromine on the end opposite of it to form the ring? The hint also talks about a charged species in product A, that is also throwing me off. Would the Nitrogen be the charged atom?

I am assuming the nitrogen is charged. I suggest you review the Hoffman chemistry. Does it not include alkylation reactions of nitrogen? This problem is about nitrogen alkylation. If so, what are the possible products? If ammonia reacted one time with 1,5-dibromopentane, it would give 5-bromopentane-1-amine ammonium salt. If that were to react with ammonia, it could give ammonium bromide. What might happen with the bromoamine? How could you get a ten carbon compound with a charge on the nitrogen (plus 3x NH4Br)

Re Hoffman
If you treat a bromide with silver oxide, you will get silver bromide (ppt) and the hydroxide salt of the amine. If A is treated with NaOH, you will have Hoffman conditions plus NaBr and water. While that may not be optimal, I cannot think why it could not effect the elimination.