Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Exploring allene chemistry using phosphorus-based allenes as scaffolds
Ist Teil von
Pure and applied chemistry, 2017-03, Vol.89 (3), p.367-377
Ort / Verlag
Berlin: De Gruyter
Erscheinungsjahr
2017
Quelle
EZB Electronic Journals Library
Beschreibungen/Notizen
In this paper, we review some of our results on cycloaddition and cyclization reactions of allenylphosphonates/and allenyl phosphine oxides. Thus nitro-substituted propargylic alcohols react with P(III)–Cl substrates to lead to unprecedented phosphono-benzazepines or -hydroxyindolinones. A similar reaction using a higher stoichiometry of P(III)–Cl precursor has led to the first observation of spontaneous resolution by crystallization in allene chemistry. In the reaction of these phosphorus based allenes with diphenyl isobenzofuran (DPBF), depending on the substituents, both [α, β] and [β, γ]-cycloaddition products are formed. Extension of this work to sulfur based allenes and leading to a new [4+2] cycloadduct with DPBF is reported. A novel cyclization reaction of a functionalized allenylphosphine oxide with diethylamine leading to 3-diethylamino-4-diphenylphosphinoyl-1-naphthol is discovered. Base-catalyzed reactions of allenylphosphonates with 2-substituted benzaldehdes lead to novel thiochromans, chromenes, and quinolines. Allenylphosphonates undergo phosphonylation in the presence of tetrabutyl ammonium fluoride (TBAF). Vinyl azides derived from allenylphosphonates undergo thermolysis to form bis-phosphonopyrazines. [Pd]-catalyzed reactions of allenes with 2-iodophenols, 2-iodobenzyl alcohol and 3-iodo-indole-2-carboxylic acids lead to a variety of benzofurans, benzopyrans and benzopyranones, respectively.