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Reaction discovery employing macrocycles: transannular cyclizations of macrocyclic bis-lactams.

ABSTRACT: Macrocyclic bis-lactams have been synthesized by cyclodimerization of homoallylic amino esters employing a Zr(IV)-catalyzed ester-amide exchange protocol. Base-mediated transannular cyclizations 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 addition pathway.

SUBMITTER: Han C

PROVIDER: S-EPMC2774802 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

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Reaction discovery employing macrocycles: transannular cyclizations of macrocyclic bis-lactams.

Han Chong C Rangarajan Sathish S Voukides Alicia C AC Beeler Aaron B AB Johnson Richard R Porco John A JA

Organic letters 20090101 2

Macrocyclic bis-lactams have been synthesized by cyclodimerization of homoallylic amino esters employing a Zr(IV)-catalyzed ester-amide exchange protocol. Base-mediated transannular cyclizations 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 addition pathway. ...[more]

PMID: 19102683

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