Understanding the Mechanism of the Divergent Reactivity of Non-Heteroatom-Stabilized Chromium Carbene Complexes with Furfural Imines: Formation of Benzofurans and Azetines

  1. Funes-Ardoiz, I. 1
  2. González, J. 2
  3. Santamaría, Javier D.. 2
  4. Sampedro, D. 1
  1. 1 Universidad de La Rioja
    info

    Universidad de La Rioja

    Logroño, España

    ROR https://ror.org/0553yr311

  2. 2 Universidad de Oviedo
    info

    Universidad de Oviedo

    Oviedo, España

    ROR https://ror.org/006gksa02

Revista:
Journal of Organic Chemistry

ISSN: 0022-3263

Año de publicación: 2016

Volumen: 81

Número: 4

Páginas: 1565-1570

Tipo: Artículo

DOI: 10.1021/ACS.JOC.5B02729 SCOPUS: 2-s2.0-84959019610 WoS: WOS:000370768000024 GOOGLE SCHOLAR

Otras publicaciones en: Journal of Organic Chemistry

Resumen

(Chemical Equation Presented) The mechanisms of the reaction between non-heteroatom-stabilized alkynyl chromium carbene complexes prepared in situ and furfural imines to yield benzofurans and/or azetines have been explored by means of density functional theory method calculations. The reaction proceeds through a complex cascade of steps triggered by a nucleophilic addition of the imine nitrogen atom. The formation of two benzofuran regioisomers has been explained in terms of competitive nucleophilic attacks to different positions of the carbene complex. Each of these regioisomers can be obtained as the major product depending on the starting materials. The overall sequence could be controlled to yield benzofurans or azetines by adjusting the substituents present in the initial carbene complex. This mechanistic information allowed for the preparation of new benzofurans and azetinylcarbenes in good yields. © 2016 American Chemical Society.