[flapjack]

Can't seem to figure this one out. Any help would be appreciated

The following reaction sequence was performed: Substance A was reacted with sodium borohydride (in ethanol) and the resulting substance B was then treated with 48% HBr, yielding substance C. This was then reacted with concentrated NaOH in ethanol to give a product D. Analysis of D showed a molecular formula of C5H8. A spot test with deep purple acidic KMnO4 solution on A produced no reaction. A spot test with deep purple acidic KMnO4 solution on B produced a colourless solution with a brown precipitate. Oxidation of D yielded a symmetrical diacid.

What is the name of compound A?

[Furanone]

Welcome to the forum, amac9102!

There will be many people here on the forum that will know this for sure, but they won't want to help until you have offered some of your own thoughts on it based on the information given, since it is a forum rule to not complete homework questions for others, but to aid them in solving the problems for themselves.

This looks like a fun puzzle with lots of clues, so what can you tell so far with all the information that is provided?

[orgopete]

Let's start with D, C5H8. Its oxidation gives a diacid. What could the structure of D be?