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Carbonium vs. carbenium ion-like transition state geometries for carbocation cyclization - how strain associated with bridging affects 5-exo vs. 6-endo selectivity.

ABSTRACT: Quantum chemical calculations are used to explore the origins of regioselectivity for proton-, Pt(II)- and Pd(II)-promoted cyclizations of 1,5-hexadienes, 5-aminoalkenes, and allylic acetimidates. The strain associated with achieving carbonium ion-like transition state geometries is shown to be a key factor in controlling 5-exo vs. 6-endo selectivity.

SUBMITTER: Gutierrez O

PROVIDER: S-EPMC3882196 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Carbonium vs. carbenium ion-like transition state geometries for carbocation cyclization - how strain associated with bridging affects 5-exo vs. 6-endo selectivity.

Gutierrez Osvaldo O Harrison Jason G JG Felix Ryan J RJ Guzman Fernando Cortés FC Gagné Michel R MR Tantillo Dean J DJ

Chemical science 20131001 10

Quantum chemical calculations are used to explore the origins of regioselectivity for proton-, Pt(II)- and Pd(II)-promoted cyclizations of 1,5-hexadienes, 5-aminoalkenes, and allylic acetimidates. The strain associated with achieving carbonium ion-like transition state geometries is shown to be a key factor in controlling 5-exo vs. 6-endo selectivity. ...[more]

PMID: 24404374

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