Intermolecular and regioselective access to polysubstituted benzo- and dihydrobenzo[c]azepine derivatives: Modulating the reactivity of group 6 non-heteroatom-stabilized alkynyl carbene complexes

  1. González, Jairo. 2
  2. Gõmez, Aránzazu. 2
  3. Funes-Ardoiz, I. 1
  4. Santamaría, J. 2
  5. 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:
Chemistry - A European Journal

ISSN: 0947-6539

Año de publicación: 2014

Volumen: 20

Número: 23

Páginas: 7061-7068

Tipo: Artículo

DOI: 10.1002/CHEM.201400281 SCOPUS: 2-s2.0-84901508769 WoS: WOS:000337574800030 GOOGLE SCHOLAR lock_openAcceso abierto editor

Otras publicaciones en: Chemistry - A European Journal

Resumen

We highlight the versatility of non-heteroatom-stabilized tungsten-carbene complexes 3 synthesized in situ, which have been used in a modular approach to access 2-benzazepinium isolable intermediates 5. By employing very mild conditions, benzazepinium derivatives 5 have been obtained in high yield from simple compounds, such as acetylides 2, Fischer-type alkoxycarbenes 1, and phenylimines 4. The process, involving a formal [4+3] heterocycloaddition, occurs in a totally regioselective manner, which differs from the approach previously observed in similar procedures for other carbene analogues. This work, which involves three components, reveals a control of the reactivity of non-heteroatom-stabilized carbene complexes 3 ([4+3] vs. [2+2]- heterocycloaddition reactions) depending on the acetylide substitution pattern. The influence of the substitution pattern in the behavior of the complexes has been computationally analyzed and rationalized. Finally, elaboration of the 2-benzazepinium intermediates allows access to 3H-benzo[c]azepines 6 and 3H-1,2-dihydrobenzo[c]azepines 7-9 with high control of the substitution of the nine positions of the heterocycle. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.