title: Understanding the Mechanism of the Divergent Reactivity of Non-Heteroatom-Stabilized Chromium Carbene Complexes with Furfural Imines: Formation of Benzofurans and Azetines.
abstract: 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.
authors.affiliation: Department of Chemistry, Center for Research in Chemical Synthesis (CISQ), University of La Rioja , Madre de Dios, 53, 26006 Logroño, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Funes-Ardoiz
authors.affiliation: Department of Organic and Inorganic Chemistry and University Institute of Organometallic Chemistry "Enrique Moles", University of Oviedo , C/Julián Clavería, 8, 33006 Oviedo, Spain.
authors.forename: Jairo
authors.initials: J
authors.lastname: González
authors.affiliation: Department of Organic and Inorganic Chemistry and University Institute of Organometallic Chemistry "Enrique Moles", University of Oviedo , C/Julián Clavería, 8, 33006 Oviedo, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Santamaría
authors.affiliation: Department of Chemistry, Center for Research in Chemical Synthesis (CISQ), University of La Rioja , Madre de Dios, 53, 26006 Logroño, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Sampedro