title: Ruthenium-catalyzed functionalization of pyrroles and indoles with propargyl alcohols.
abstract: Several ruthenium-catalyzed atom-economic transformations of propargyl alcohols with pyrroles or indoles leading to alkylated, propargylated, or annulated heteroaromatics are reported. The mechanistically distinct reactions are catalyzed by a single ruthenium(0) complex containing a redox-coupled dienone ligand. The mode of activation regarding the propargyl alcohols determines the reaction pathway and depends on the alcohols' substitution pattern. Secondary substrates form alkenyl complexes by a 1,2-hydrogen shift, whereas the transformation of tertiary substrates involves allenylidene intermediates. 1-Vinyl propargyl alcohols are converted by a cascade allylation/cyclization sequence. The environmentally benign processes are of broad scope and allow the selective synthesis of highly functionalized pyrroles and indoles generating water as the only waste product.
authors.affiliation: Institut für Chemie, Otto-von-Guericke-Universität Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany.
authors.forename: Nora
authors.initials: N
authors.lastname: Thies
authors.forename: Cristian G
authors.initials: CG
authors.lastname: Hrib
authors.forename: Edgar
authors.initials: E
authors.lastname: Haak