u/ArachnidSufficient91

Hello,

Attached is an old exam question that I am struggling with. I believe I should go via a Zimmerman-Traxler transition state and since we have a trans enolate (11), I will end up with an anti aldol. However, no reactant that I have worked with prior has had such large groups attached to the carbonyl. I understand that the enolate reacts with the ketone and not the amide. I don't know how to determine the orientation of the ketone's substituents in 10 in the Zimmerman-Traxler. Which one will be pseudo-equatorial and which one will be pseudo-axial? Will the "amide side" be pseudo-axial, since there are 2 carbons until the bulky group as opposed to 1 (= less sterics)?

The exam question doesn't give a whole lot of points so I don't know if I'm complicating things here.

Thank you in advance!

I really don't know how to solve this.

The product looks like a hybrid of an aldol addition reaction and Claisen condensation reaction, but we have an ester in the product, an alcohol group, and stereochemistry. I've been googling around and the Reformatsky reaction seems to produce similar products, but not including base and it isn't a reaction that's been mentioned in my course anyway.

Any help is greatly appreciated! Thank you in advance!