Question

5. Provide a detailed mechanism including curved arrows showing electron flow, intermediate structures, formal charges, and reaction arrows. Be sure to show all relevant bonds. Then, answer the associated question. (11 points) TIP: This is much more straightforward than it looks. It's just two Michael Addition reactions. SiMey Me,Si Me 1. (2 equiv base), THF -78 °C to 0 °C -Me Me Me Me 2. H2O, HCI OMe Mel COMe Me Me td .OMe H-0-1 a. Lithium hexamethyldisilazide (LiHMDS) operates as a base in this mechanism, Another name for this is lithium bis(trimethylsilyl)amide or abbreviated (TMS)2NLi where TMS is trimethylsilyl. It is also a bulky base like LDA. What would be one advantage to using LUHMDS over LDA aside from slightly increased bulk? (1 point) TIP: Consider the pK values in DMSO. Use the tables provided on Carmen for help with this. b Is quantitative enolate formed/tavored in the reaction above? Yes or no is fine as I assume you've done the work to answer the above question. (1 point)

Answer 1

Gve nupbeing ре те fo betieo undesstanding orme G Me oe Coome Li me me me G me Fisst michael addition Cs autaGK on Cio GOOme 8 me Second micha addiriorn atta ck on С1 me pe COome me HCl, Ha0 COome