Syntheses of Heterocycles via Alkyne Cycloadditions Catalyzed by Cyclopentadienylruthenium-Type Complexes

Abstract

Transition-metal catalysis not only simplifies molecular assemblies by reducing the synthetic steps but also decreases waste production, thus accomplishing an efficient and environmentally benign synthesis of heterocycles.Ruthenium catalysis has made significant progress in the past decades, and its application to heterocycle synthesis has become one of the major research topics.In particular, organoruthenium complexes with a cyclopentadienyl-type ligand have been successfully utilized in various carbon-carbon and carbon-heteroatom bond formations. This review extensively surveys the synthetic methods of fiveand six-membered heterocycles via the ruthenium-catalyzed cycloadditions of alkynes with other unsaturated compounds. The applications of the ruthenium-catalyzed heterocycle synthesis are also briefly outlined.

Bimetallic Nanocatalysts in Glycerol for Applications in Controlled Synthesis. A Structure–Reactivity Relationship Study

“…In relation to the copper reactivity, we opted for the Cu-catalyzed azide alkyne cycloaddition (CuAAC), powerful means for the regioselective synthesis of 1,2,3-triazoles, valuable motifs in many fields such as biochemistry, organic synthesis, medicinal chemistry, and materials. − Since the first Cu-catalyzed works described independently by Sharpless and Meldal in 2002, many Cu-based catalytic systems have been described, − but also those involving other metals. − Copper-based nanoparticles have been less studied, in particular those using well-defined nanoparticles; ,− the formation of Cu-based nanoparticles promotes the AAC reaction thanks to the cooperative effect between neighboring metal centers. In this frame, we desired to evaluate the effect triggered by palladium on copper in this well-known reaction.…”

Ruthenium-Catalyzed Azide Alkyne Cycloaddition Reaction: Scope, Mechanism, and Applications

“…While this ruthenium-catalyzed azide alkyne cycloaddition (RuAAC) has as yet not found as prevalent use as the CuAAC reaction, reports of its application are increasing rapidly. Although the RuAAC reaction has been briefly mentioned in several reviews on triazole formation − and metal-catalyzed reactions, − a comprehensive survey focused solely on RuAAC is now essential. This Review covers the initial reports of the ruthenium-catalyzed azide alkyne cycloaddition from 2005 and 2008, as well as the synthetic development, mechanistic studies, and applications of the RuAAC reaction up until September 2016.…”

“…While this ruthenium-catalyzed azide alkyne cycloaddition (RuAAC) has as yet not found as prevalent use as the CuAAC reaction, reports of its application are increasing rapidly. Although, the RuAAC reaction has been briefly mentioned in several reviews on triazole formation [13][14][15][16][17][18][19][20][21][22][23] and metalcatalyzed reactions, [24][25][26] by now a comprehensive survey focused solely on RuAAC is needed.…”

DFT Investigation of the η6 ⇌ η6-Inter-ring Haptotropic Rearrangement of the Group 8 Metals Complexes [(graphene)MCp]+ (M = Fe, Ru, Os)

“…No data on the dependence of activation parameters on a metal (the difference from Fe via Ru to Os) have been obtained as well as no effects of solvents on the activation parameters of the metal complex HRs. We believe that knowledge of these data will compose a very important part of the organometallic chemistry of graphene which is well-known to be a highly competitive, rapidly developing, and promising area of research. − The strong interest in obtaining these data can be clearly understood from the fact of numerous examples of using cyclopentadienyl complexes of the group 8 metals as catalysts (Fe, − Ru ,− ) or valuable precursors for different organometallic compounds (Os). − Motivated by these examples, it would be of high interest to elucidate potential catalytic activity and chemical reactivity in general of the group 8 OMG complexes on the graphene surface. It should be noticed that, in a more general way, in the course of an inter-ring haptotropic rearrangement, as was mentioned earlier, the metal encompasses unsaturation and thus becomes prone to reaction with various incoming species. − ,− Furthermore, it is very important to mention that large PAHs such as graphene and nanotubes were shown to have intrinsic anticancer activity. − Also, numerous arene complexes of Fe, , Ru, ,,,− and Os have been proven to possess anticancer activity.…”