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Synthesis of N-H Bearing Imidazolidinones and Dihydroimidazolones Using Aza-Heck Cyclizations.

ABSTRACT: The synthesis of unsaturated, unprotected imidazolidinones via an aza-Heck reaction is described. This palladium-catalyzed process allows for the cyclization of N-phenoxy ureas onto pendant alkenes. The reaction has broad functional group tolerance, can be applied to complex ring topologies, and can be used to directly prepare mono- and bis-unprotected imidazolidinones. By addition of Bu4 NI, dihydroimidazolones can be accessed from the same starting materials. Improved conditions for preparing unsaturated, unprotected lactams are also reported.

SUBMITTER: Xu F

PROVIDER: S-EPMC6141047 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Synthesis of N-H Bearing Imidazolidinones and Dihydroimidazolones Using Aza-Heck Cyclizations.

Xu Feiyang F Shuler Scott A SA Watson Donald A DA

Angewandte Chemie (International ed. in English) 20180819 37

The synthesis of unsaturated, unprotected imidazolidinones via an aza-Heck reaction is described. This palladium-catalyzed process allows for the cyclization of N-phenoxy ureas onto pendant alkenes. The reaction has broad functional group tolerance, can be applied to complex ring topologies, and can be used to directly prepare mono- and bis-unprotected imidazolidinones. By addition of Bu<sub>4</sub> NI, dihydroimidazolones can be accessed from the same starting materials. Improved conditions for ...[more]

PMID: 30125443

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