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Asymmetric Synthesis of 2,3-Dihydrobenzofurans by a [4+1] Annulation Between Ammonium Ylides and In Situ Generated o-Quinone Methides.

ABSTRACT: A highly enantio- and diastereoselective [4+1] annulation between in situ generated ammonium ylides and o-quinone methides for the synthesis of a variety of 2,3-dihydrobenzofurans has been developed. The key factors controlling the reactivity and stereoselectivity were systematically investigated by experimental and computational means and the energy profiles obtained provide a deeper insight into the mechanistic details of this reaction.

SUBMITTER: Meisinger N

PROVIDER: S-EPMC5419452 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of 2,3-Dihydrobenzofurans by a [4+1] Annulation Between Ammonium Ylides and In Situ Generated o-Quinone Methides.

Meisinger Nicole N Roiser Lukas L Monkowius Uwe U Himmelsbach Markus M Robiette Raphaël R Waser Mario M

Chemistry (Weinheim an der Bergstrasse, Germany) 20170327 21

A highly enantio- and diastereoselective [4+1] annulation between in situ generated ammonium ylides and o-quinone methides for the synthesis of a variety of 2,3-dihydrobenzofurans has been developed. The key factors controlling the reactivity and stereoselectivity were systematically investigated by experimental and computational means and the energy profiles obtained provide a deeper insight into the mechanistic details of this reaction. ...[more]

PMID: 28165173

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