Reaction Discovery Employing Macrocycles: Transannular Cyclizations of Macrocyclic Bis-lactams
作者:Chong Han、Sathish Rangarajan、Alicia C Voukides、Aaron B. Beeler、Richard Johnson、John A. Porco
DOI:10.1021/ol802729f
日期:2009.1.15
Macrocyclic bis-lactams have been synthesized by cyclodimerization of homoallylic amino esters employing a Zr(IV)-catalyzed ester-amide exchange protocol. Base-mediated transannularcyclizations have been identified to access both bicyclic [5-11] and tricyclic [5-8-5] frameworks in good yield and diastereoselectivity. Preliminary mechanistic studies support an olefin isomerization−intramolecular conjugate