Fused Ring via FC Acylation

[thaibrawler]

hmm blike could probably heelp.

 

ok the question is to transform benzene into a fused ring. I dont know how to name the product but this is the reaction to obtain the product.

 

Starting from benzne

A/add maleic anhydride1/XS ALCL3 heat, 2/water

B/reduce via Zn(Hg) HCL and heat

C/ PCL5

D/ 1/XS ALCL3 2/ water(this creates the fused ring)

 

My question is the mechanism. For A>B I have the electron from the benzene attack one of the carbonyl from maleic anhydirde whcih gives the o a (-) charge with a alcl3 attached to it. No resonance thus far right? The O takes a proton form the water and you are left with OH.

 

Now to get form C->D the cl attacks the alcl3 and the alcl3 is then left leaving an acylium ion whcih resonates. the benzene pi e- attacks it leaving a (+) charge in the benzene ring.<The cl attacks the h to reform the double bond> or does the h20 attacks the h to form h30? then the reaction is finish.

 

the product should have a benzene ring on one end and directly fused to it another benzene with a c=o attached.

 

thanks