The asymmetric synthesis of 2, 2-dialkyl carboxylic esters and 2, 2-disubstituted dihydronaphthalenes

AI Meyers, RH Wallace, M Harre…

Index: Meyers, A. I.; Wallace, Richard H.; Harre, Michael; Garland, Robert Journal of Organic Chemistry, 1990 , vol. 55, # 10 p. 3137 - 3143

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Citation Number: 15

Abstract

The bicyclic lactams derived from (S)-valinol and 3-benzoylpropionic acid or levulinic acid are useful chiral precursors to the title compounds. Metalation of bicyclic lactams 1 or 4 and alkylation followed by acidic hydrolysis leads to racemic 2-alkyl carboxylic acids. However, sequential metalation-alkylation to 2, 2-dialkyl bicyclic lactams 2 and 5 furnishes these systems with good diastereoselectivity. Treatment of 5 with triflic acid causes a facile ...