organic synthesis

May 2017
1
0
england
Hi, I'm doing some past exam questions and have got stuck on the attached question.
Although I think I've got a solution to part I) (Witting reaction, followed by reaction with OSO4 and then and then reacting with a dibromide compound) I am very stuck on part b.

For part b I have tried a substituting the Bromo group for OH, oxidising to a ketone and then reacting with Ph-MgBr but this still leaves me with an extra CH3. Any help pointing in the right direction would be appreciated.
 

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