A two-step four-component queuing cascade involving a Heck coupling, pi-allylpalladium trapping and Diels-Alder reaction


Yucel B. , ARVE L., DE MEIJERE A.

TETRAHEDRON, vol.61, no.48, pp.11355-11373, 2005 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 61 Issue: 48
  • Publication Date: 2005
  • Doi Number: 10.1016/j.tet.2005.09.014
  • Title of Journal : TETRAHEDRON
  • Page Numbers: pp.11355-11373

Abstract

Palladium-catalyzed cross-coupling of bicyclopropylidene (1) with iodoethene (11) in the presence of a secondary amine 12 provides allylidenecyclopropanes 13 which undergo immediate Diels-Alder reactions upon addition of dienophiles 14-18 to provide 8- (1'-aminoethyl)-substituted spiro[2.5]oct-7-ene derivatives 23a-26a in 29-66% yield. The same one-pot, two-step queuing cascade can be carried out with other iodoalkenes including cyclic ones and with cyclic dienophiles such as N-arylmaleinamides 19-22 and N-phenyl-triazolinedione 37 to furnish highly substituted spiro[2.5]oct-4-enes and spirocyclopropanated heterobicycles 47a-49a, 41a-46a (17-50%). Spirocyclopropanated heterobicycles such as 55, 56 (25 and 38% yield, respectively) can also be obtained by an inter-intra-intraintermolecular version of this queuing cascade involving 1-hydroxyethyl- and 1-aminoethyl -substituted iodoethenes 53, 54. (c) 2005 Elsevier Ltd. All rights reserved.