Efficient Stereoselective Syntheses of Constrained Glutamates via Michael‐Induced Ring Closing Reactions

Abstract

Keywords: Chelated enolates / Constrained amino acids / Glutamates / Michael addition / Michael-induced ring closure (MIRC)Zn-chelated glycine ester enolates are highly efficient nucleophiles for the synthesis of conformationally constrained glutamates via domino sequences of Michael additions and subsequent ring closures (MIRC). This protocol allows the generation of 3-6-membered ring systems in high yields and

Regio- and Stereocontrol in the Michael-Initiated Ring-Closure Reactions of γ,δ-Epoxy-α,β-unsaturated Esters, Ketones, Sulfones, and Amides

“…The protocol has been successfully applied for the construction of three-, four-, five-, six-, and seven-membered rings. Michael acceptors containing a leaving group in the γ-position are largely limited to γ-halo-α,β-unsaturated esters, ,, ketones, , sulfones, , and nitroalkenes since participation of γ,δ-epoxy-α,β-unsaturated substrates in MIRC reactions have been limited to bis-activated alkenes , or use of dithianyl anions as other organolithium and Grignard reagents failed.…”