Question

CHM 2430 FA 2017 0 LDA - H2O 0 Na OEt H20 Intramolecular Aldol CHI 120 1. LDA β-keto ester 1. Na OEt, EtoH 2. H30* C7H120 1. LDA 0ヘ β-keto ester- 10. provide the mjor organic product for each box (via each transformation): (5 pts, 0.25 pt each) 1. LiAIH4 H30* NH2 cat. Hyo cat. H3o* CH3CH2-MgBr 2. H3o

Answer 1

In first step it is shown only one LDA and not 2 eq. LDA, hence only one o-proton is abstracted to give aldol product он LDA H20 CH H20 Na OEt Нас CH CH CH CH 1) LDA H2C 2) H30+ CH 3 The B-ketoester formed undergoes hydrolysis and 1) Na OEt, EtoH o decarboxylation. Hence the product has less number of carbons. The acidity of a-proton without CH3 group is more then other 2) H30+

Esters that have only one a-hydrogen do not undergo the H2C 1) LDA OCH usual Claisen condensation. CH3 2) H30+ ethyl 2-methylpropano ate ethyl acetate

H30+ OH O Li 1. LiAIH 1,04 NH2 cat. H30 cat. H2o CH,CHz-MgBr 2. H,o CH OH CH