Lithium Binaphtholate-Catalyzed Michael Reaction of Malonates with Maleates and Its Application to the Enantioselective Synthesis of Tricarboxylic Acid Derivatives
The Michael reaction of malonates with maleates afforded the corresponding adducts in high yields with high enantioselectivities (up to 98% enantiomeric excess (ee)) by using dilithium 3,3'-dichlorobinaphtholate as a catalyst. The obtained Michael adducts could be converted to optically active tricarboxylic acid (TCA) derivatives via the Krapcho reaction.
Enantioselective Lewis Acid Catalyzed Michael Reactions of Alkylidene Malonates. Catalysis by <i>C</i><sub>2</sub>-Symmetric Bis(oxazoline) Copper(II) Complexes in the Synthesis of Chiral, Differentiated Glutarate Esters
作者:David A. Evans、Tomislav Rovis、Marisa C. Kozlowski、C. Wade Downey、Jason S. Tedrow
DOI:10.1021/ja002246+
日期:2000.9.1
C2-symmetricbis(oxazoline)−Cu(II) complexes 1 catalyze the Mukaiyama Michael reaction of alkylidene malonates and enolsilanes. The use of hexafluoro-2-propanol is essential to induce catalyst turnover. High enantioselectivities are exhibited by bulky alkylidene malonate β-substituents using catalyst 1a. The glutarate ester products are readily decarboxylated to provide chiral 1,5-dicarbonyl synthons