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Imidazolidin-4-ones via (3+2) cycloadditions of aza-oxyallyl cations onto (E)-Narylideneanilines.

ABSTRACT: In the course of our studies on the chemistry of oxyallyl species we uncovered a new (3+2) cycloaddition of aza-oxyallyl systems, generated in situ from N-benzyloxy-2-chloroamides in the presence of NEt₃, onto N-arylimines yielding imidazolidin-4-ones in moderate to good yields. The cycloadditions are regioselective. Computational modelling using DFT at the M062×/6-311+G** level is in support the observed regioselectivities. Although the path to the trans imidazolin-4-one is favored, the cis product is preferred by almost 8 kcal/mol and could be formed by base-catalyzed epimerization. All products were isolated by chromatography and characterized by means of their FTIR, NMR and HRMS data.

SUBMITTER: Eyilcim O

PROVIDER: S-EPMC6236675 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Imidazolidin-4-ones via (3+2) cycloadditions of aza-oxyallyl cations onto (E)-Narylideneanilines.

Eyilcim Oznur O Issever Sezin S Ocal Nuket N Gronert Scott S Erden Ihsan I

Tetrahedron letters 20180905 41

In the course of our studies on the chemistry of oxyallyl species we uncovered a new (3+2) cycloaddition of aza-oxyallyl systems, generated in situ from N-benzyloxy-2-chloroamides in the presence of NEt3, onto N-arylimines yielding imidazolidin-4-ones in moderate to good yields. The cycloadditions are regioselective. Computational modelling using DFT at the M062×/6-311+G** level is in support the observed regioselectivities. Although the path to the trans imidazol ...[more]

PMID: 30449908

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