Question

1. CH3CH2COCl, AlCl3
followed by workup
2. MCPBA

with a benzene starting material

how does mcpba add in this reaction?

Answer 1

What do you got so far?

Answer 2

Then something interesting happens. the lone pair of electrons from the chlorine attacks the AlCl3, which serves as a lewis acid.

Answer 3

This actually gives us a more stable intermediate. if you think about it, Friedel-crafts alkylation is not that great because we often get a mixture of products. here we'll only get one product. probably why the guy never got a nobel prize