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Preparation and Diels-Alder reactions of 1'-heterosubsituted vinylimidazoles.

ABSTRACT: A Diels-Alder/rearrangement sequence has been pursued in our lab en route to a number of oroidin dimers. In order to access the fully substituted core of these molecules, 1',2'-disubstituted 4-vinylimidazoles were required as dienes. The preparation of a series of a 4-vinylimidazoles containing substituents on the vinyl moiety via hydroalumination/electrophilic trapping or hydrosilylation are described. These derivatives undergo Diels-Alder reactions with N-phenylmaleimide to provide the tetrahydrobenzimidazole derivatives. The cycloadducts derived from halosubstituted systems generally undergo elimination, leading to the corresponding dihydrobenzimidazole, whereas the silyl and stannyl derivatives provide the corresponding 4-substituted tetrahydrobenzimidazole.

SUBMITTER: Ray A

PROVIDER: S-EPMC4484863 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Preparation and Diels-Alder reactions of 1'-heterosubsituted vinylimidazoles.

Ray Abhisek A Mukherjee Sabuj S Das Jayanta J Bhandari Manoj K MK Du Hongwang H Yousufuddin Muhammed M Lovely Carl J CJ

Tetrahedron letters 20150601 23

A Diels-Alder/rearrangement sequence has been pursued in our lab en route to a number of oroidin dimers. In order to access the fully substituted core of these molecules, 1',2'-disubstituted 4-vinylimidazoles were required as dienes. The preparation of a series of a 4-vinylimidazoles containing substituents on the vinyl moiety via hydroalumination/electrophilic trapping or hydrosilylation are described. These derivatives undergo Diels-Alder reactions with <i>N</i>-phenylmaleimide to provide the ...[more]

PMID: 26139945

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