You did not have OH group, it is O-. Try protection of OH group.
Sorry AWK but the exercise test says :
1. 2 equivalent LDA
(Don't use protector group)
So it could be -O-
( ok) or OLi ...
But in order to have COOEt in anti with the alcoholic OH group in the final product the electrophile should attack from the same side of O-
If the electrophile attacks from the OPPOSITE side of O- (like I did ) I got -COOEt and OH in anti...not in syn
So it should attack from the same side of the oxygen?
Perhaps the OLi is less bulky then the -CH3 downside?