• alkyne
  • In this study, a dynamic coordination capsule constructed by a flexible macrocycle and silver( I ) ions is applied to trigger one-step or cascade cyclization reactions for various alkyne substrates, finally leading to five unprecedented polysilver heteroaromatic intermediates (including indole, quinoline, benzocarbazole and 2,2′-biindole). (rsc.org)
  • tandem
  • A novel palladium( II ) catalysed tandem cyclisation of substituted 2-alkenylphenyl alkynones gives substituted 2-vinyl indenones and 6,5,6-fused tricyclic lactone skeletons (pyrones), in one-pot. (rsc.org)
  • substrates
  • Similarly, β-substitution directed inward restricts the s-trans conformation so severely that E-Z isomerization has been shown to occur in advance of cyclization on a wide range of substrates, yielding the trans cyclopentenone regardless of initial configuration. (wikipedia.org)
  • stable
  • Although the exo radical is less thermodynamically stable than the endo radical, the more rapid exo cyclization is rationalized by better orbital overlap in the chair-like exo transition state (see below). (wikipedia.org)
  • Stabilizing the initially formed radical with electron-withdrawing groups provides access to more stable 6-endo cyclization products preferentially. (wikipedia.org)
  • similar
  • Under similar conditions, the Prins cyclization of six alcohols containing an endocyclic double bond (primary, secondary, or tertiary) led to dihydropyrans in 52%-91% yield. (mdpi.com)
  • general
  • Though cyclizations following the general template above had been observed prior to Nazarov's involvement, it was his study of the rearrangements of allyl vinyl ketones that marked the first major examination of this process. (wikipedia.org)
  • vinyl
  • See Interrupted cyclizations below) Along this same vein, allenyl vinyl ketones of the type studied extensively by Marcus Tius of the University of Hawaii show dramatic rate acceleration due to the removal of β-hydrogens, obviating a large amount of steric strain in the s-cis conformer. (wikipedia.org)
  • generation
  • They usually proceed in three basic steps: selective radical generation, radical cyclization, and conversion of the cyclized radical to product. (wikipedia.org)
  • product
  • In the case of the former, a doubly cyclised product was isolated from cyclisation with solid FeCl 3 , while the latter gives a rearranged 3 H -pyrrole upon irradiation. (rsc.org)