Browse
Submit Data
Databases
API
Help

Dataset Information

25 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Microwave-Assisted Dehydrogenative Cross Coupling Reactions in ?-valerolactone with a Reusable Pd/?-cyclodextrin Crosslinked Catalyst.

ABSTRACT: Transition-metal mediated C?H bond activation and functionalization is one of the most straightforward and powerful tools in modern organic synthetic chemistry. Oxidative C?H/C?H coupling reactions between two (hetero)arenes under heterogeneous catalysis may be a valuable means for the production of a plethora of bi(hetero)aryls, and one that adheres to the increasing demand for atom-economic and sustainable chemistry. We have therefore developed a reusable heterogeneous catalytic system, which is based on Pd cross-linked ?-cyclodextrin, to perform an efficient microwave-assisted oxidative C?H/C?H cross coupling process between benzothiazoles and methyl thiophene in the presence of green solvents.

SUBMITTER: Tabasso S

PROVIDER: S-EPMC6359118 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Microwave-Assisted Dehydrogenative Cross Coupling Reactions in γ-valerolactone with a Reusable Pd/β-cyclodextrin Crosslinked Catalyst.

Tabasso Silvia S Gaudino Emanuela Calcio EC Acciardo Elisa E Manzoli Maela M Giacomino Agnese A Cravotto Giancarlo G

Molecules (Basel, Switzerland) 20190114 2

Transition-metal mediated C⁻H bond activation and functionalization is one of the most straightforward and powerful tools in modern organic synthetic chemistry. Oxidative C⁻H/C⁻H coupling reactions between two (hetero)arenes under heterogeneous catalysis may be a valuable means for the production of a plethora of bi(hetero)aryls, and one that adheres to the increasing demand for atom-economic and sustainable chemistry. We have therefore developed a reusable heterogeneous catalytic system, which ...[more]

PMID: 30646596

Similar Datasets

Avoiding hot-spots in Microwave-assisted Pd/C catalysed reactions by using the biomass derived solvent ?-Valerolactone.

Project description:Herein, we report the use of ?-valerolactone as a new biomass-derived reaction medium for microwave assisted organic synthesis. The interaction of this solvent with microwaves and its heating profile under microwave irradiation has been fully characterized for the first time, demonstrating its stability and the applicability in microwave assisted Pd/C catalysed reactions avoiding the arcing phenomena frequently observed in these conditions. The use of ?-valerolactone demonstrated to be compatible with aliphatic and aromatic amines in the hydrogen transfer Pd/C mediated synthesis of benzimidazoles.

| S-EPMC6043498 | biostudies-literature

A multiligand based Pd catalyst for C-N cross-coupling reactions.

Project description:An alternative approach to catalyst development, which led to a Pd catalyst based on two biarylphosphine ligands for C-N cross-coupling reactions, is reported. By effectively being able to take the form of multiple catalysts this system manifests the best properties that catalysts based on either of the two ligands exhibit separately and displays the highest reactivity and substrate scope of any system that has been reported to date for these reactions.

| S-EPMC2995307 | biostudies-literature

Palladium-catalyzed Sonogashira coupling reactions in ?-valerolactone-based ionic liquids.

Project description:It was demonstrated that the ?-valerolactone-based ionic liquid, tetrabutylphosphonium 4-ethoxyvalerate as a partially bio-based solvent can be utilized as alternative reaction medium for copper- and auxiliary base-free Pd-catalyzed Sonogashira coupling reactions of aryl iodides and functionalized acetylenes under mild conditions. Twenty-two cross-coupling products were isolated with good to excellent yields (72-99%) and purity (>98%). These results represent an example which proves that biomass-derived safer solvents can be utilized efficiently in common, industrially important transformations exhibiting higher chemical and environmental efficiency.

| S-EPMC6902853 | biostudies-literature

The design, synthesis and validation of recoverable and readily reusable siloxane transfer agents for Pd-catalyzed cross-coupling reactions.

Project description:The development of competent, recoverable and reusable 1-oxa-2-silacyclopentene (siloxane) transfer agents for Pd-catalyzed cross-coupling reactions (CCRs) of organolithium reagents with aryl and alkenyl iodides has been achieved. Drawbacks of the first-generation siloxane-transfer agent (1), relating to facile recovery for potential recycling, have been addressed.

| S-EPMC3762947 | biostudies-literature

A Copper-Based Metal-Organic Framework as an Efficient and Reusable Heterogeneous Catalyst for Ullmann and Goldberg Type C-N Coupling Reactions.

Project description:A highly porous metal-organic framework (Cu-TDPAT), constructed from a paddle-wheel type dinuclear copper cluster and 2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine (H?TDPAT), has been tested in Ullmann and Goldberg type C-N coupling reactions of a wide range of primary and secondary amines with halobenzenes, affording the corresponding N-arylation compounds in moderate to excellent yields. The Cu-TDPAT catalyst could be easily separated from the reaction mixtures by simple filtration, and could be reused at least five times without any significant degradation in catalytic activity.

| S-EPMC6332410 | biostudies-literature

Intramolecular arylation of benzimidazoles via Pd(II)/Cu(I) catalyzed cross-dehydrogenative coupling.

Project description:Electron poor benzimidazole substrates were arylated via an intramolecular cross-dehydrogenative coupling (CDC) reaction. These CDC reactions were catalyzed by a Pd(II)/Cu(I) catalyst system, capable of producing moderate yields on a large library of substrates. The substrate scope consisted of tethered arene-benzimidazoles that upon coupling, produced a fused polycyclic motif.

| S-EPMC3993984 | biostudies-literature

Amine-Functionalized Graphene Oxide-Stabilized Pd Nanoparticles (Pd@APGO): A Novel and Efficient Catalyst for the Suzuki and Carbonylative Suzuki-Miyaura Coupling Reactions.

Project description:Palladium nanoparticles (NPs) are decorated on the surface of an amine-functionalized graphene oxide (Pd@APGO) and characterized by using various analytical techniques. In this methodology, the surface of graphene oxide is modified using the amine functional groups which help stabilization and distribution of Pd NPs very well and increases the surface electron density of NPs by electron donating from amine groups. This developed catalyst shows a high catalytic activity toward the Suzuki coupling and carbonylative Suzuki-Miyaura coupling reactions at mild reaction conditions. The amine on the graphene oxide plays a very crucial role to stabilize and increase the electron density of Pd NPs and prevents the leaching of Pd metals. The Pd@APGO catalyst showed excellent catalytic activity (>90%) with a large range of substrates for both of the reactions and provides five recycle runs without the loss of its activity.

| S-EPMC6649301 | biostudies-literature

Catalyst-Free Cross-Dehydrogenative Coupling Strategy Using Air as an Oxidant: Synthesis of α-Aminophosphonates.

Project description:α-Aminophosphonates are synthesized by employing unfunctionalized starting materials using cross-dehydrogenative coupling strategy. This method does not require any catalyst and proceeds in the presence of open air as the only oxidant. Mechanistic studies revealed that the reaction is nucleophile dependent and specific to dialkyl phosphite and N-aryl tetrahydroisoquinoline derivatives.

| S-EPMC6641911 | biostudies-literature

Diacetyl as a "traceless" visible light photosensitizer in metal-free cross-dehydrogenative coupling reactions.

Project description:Minisci alkylation is of prime importance for its applicability in functionalizing diverse heteroarenes, which are core structures in many bioactive compounds. In alkyl radical generation processes, precious metal catalysts, high temperatures and excessive oxidants are generally involved, which lead to sustainability and safety concerns. Herein we report a new strategy using diacetyl (2,3-butanedione) as an abundant, visible light-sensitive and "traceless" hydrogen atom abstractor to achieve metal-free cross-dehydrogenative Minisci alkylation under mild conditions. Mechanistic studies supported hydrogen atom transfer (HAT) between an activated C(sp3)-H substrate and diacetyl. Moreover, with the assistance of di-tert-butyl peroxide (DTBP), the scope of the reaction could be extended to strong aliphatic C-H bonds via diacetyl-mediated energy transfer. The robustness of this strategy was demonstrated by functionalizing complex molecules such as quinine, fasudil, nicotine, menthol and alanine derivatives.

| S-EPMC6530541 | biostudies-literature

Ruthenium PNN(O) Complexes: Cooperative Reactivity and Application as Catalysts for Acceptorless Dehydrogenative Coupling Reactions.

Project description:The novel tridentate PNNOH pincer ligand LH features a reactive 2-hydroxypyridine functionality as well as a bipyridyl-methylphosphine skeleton for meridional coordination. This proton-responsive ligand coordinates in a straightforward manner to RuCl(CO)(H)(PPh3)3 to generate complex 1. The methoxy-protected analogue LMe was also coordinated to Ru(II) for comparison. Both species have been crystallographically characterized. Site-selective deprotonation of the 2-hydroxypyridine functionality to give 1' was achieved using both mild (DBU) and strong bases (KOtBu and KHMDS), with no sign of involvement of the phosphinomethyl side arm that was previously established as the reactive fragment. Complex 1' is catalytically active in the dehydrogenation of formic acid to generate CO-free hydrogen in three consecutive runs as well as for the dehydrogenative coupling of alcohols, giving high conversions to different esters and outperforming structurally related PNN ligands lacking the NOH fragment. DFT calculations suggest more favorable release of H2 through reversible reactivity of the hydroxypyridine functionality relative to the phosphinomethyl side arm.

| S-EPMC5770139 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data