Gold‐Catalyzed Cycloisomerizations of Functionalyzed Cyclopropyl Alkynes: the Cases of Carboxamides and Alcohols

Fernández‐García, Jesús M.; Garro, Hugo Alejandro; Fernández‐García, Laura; García‐García, Patricia; Fernández‐Rodríguez, Manuel A.; Merino, Isabel; Aguilar, Enrique

doi:10.1002/adsc.201700264

Cited by 16 publications

(6 citation statements)

References 95 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The typical shape of the Cu foil is reasonable followed by the Cu sample. The CuNi displays a typical 1s→4p pre‐edge transition but the characteristic valley between the 5sp resonances is less marked as a consequence of the (energy) smearing of the corresponding continuum states, a typical effect of alloying (the XANES spectrum is further discussed in the Supporting Information, Section 4.1.3, Figure S11) . Note however that this would occur with a rather limited quantity of Ni (Cu‐rich alloy) as the Ni K‐edge does not show a significant reduction of Ni.…”

Section: Figuresupporting

confidence: 68%

Phase‐Contact Engineering in Mono‐ and Bimetallic Cu‐Ni Co‐catalysts for Hydrogen Photocatalytic Materials

et al. 2018

View full text Add to dashboard Cite

Understanding how a photocatalyst modulates its oxidation state, size, and structure during a photocatalytic reaction under operando conditions is strongly limited by the mismatch between (catalyst) volume sampled by light and, to date, the physicochemical techniques and probes employed to study them. A synchrotron micro‐beam X‐ray absorption spectroscopy study together with the computational simulation and analysis (at the X‐ray cell) of the light‐matter interaction occurring in powdered TiO2‐based monometallic Cu, Ni and bimetallic CuNi catalysts for hydrogen production from renewables was carried out. The combined information unveils an unexpected key catalytic role involving the phase contact between the reduced and oxidized non‐noble metal phases in all catalysts and, additionally, reveals the source of the synergistic Cu‐Ni interaction in the bimetallic material. The experimental method is applicable to operando studies of a wide variety of photocatalytic materials.

show abstract

Section: Figuresupporting

confidence: 68%

Phase‐Contact Engineering in Mono‐ and Bimetallic Cu‐Ni Co‐catalysts for Hydrogen Photocatalytic Materials

et al. 2018

View full text Add to dashboard Cite

show abstract

“…6a). In addition to that a small shoulder at around 2152 cm −1 can be observed after this first reduction step which can be explained by linearly adsorbed CO on some little amounts of residual, not yet reduced PdO that appears at 2150-2160 cm −1 according to literature [29,[31][32][33][34][35][36][37]. After 473 K reduction, the signal for adsorbed CO decreased to less than 10% (Fig.…”

Section: Drifts Surface Investigationmentioning

confidence: 92%

CO oxidation as a test reaction for strong metal–support interaction in nanostructured Pd/FeO powder catalysts

Kast

Friedrich

Teschner

et al. 2015

Applied Catalysis A: General

View full text Add to dashboard Cite

a b s t r a c tA series of differently loaded palladium-iron catalysts was prepared by a controlled co-precipitation method of the nitrate precursors, in order to ensure homogeneous Pd particle size-distribution. After characterization of the pre-catalysts by various techniques, different controlled reduction conditions were applied to investigate the interactions within the Pd-iron system, containing reversible and irreversible processes like phase transformations, SMSI, sintering and alloying. Strong indications for the reversible surface decoration of the Pd nanoparticles with iron oxide species via strong metal-support interaction were found by the combined results of DRIFTS, CO-chemisorption, TEM and XPS measurements. This SMSI state was found to be unstable. It was observed independent of bulk phase or palladium particle size. Catalytic CO-oxidation was found to be a suitable test reaction for the study of the phenomenon: higher activity as well as oxidative deactivation of the SMSI state was observed by investigating the lightoff behavior in repeated, temperature-programmed cycles as well as by isothermal measurements. The instability was found to be higher in case of higher Pd dispersion. In addition, bulk properties of the Pd-Fe system, like alloying, were investigated by detailed XRD measurements.

show abstract

“…Later in 2017, using alkynyl cyclopropanamides 252 and alkynyl cyclopropylmethanols 255 as substrates, Aguilar’s group realized a controllable Au(I)-catalyzed cascade cycloisomerization of similar push–pull-type alkynyl cyclopropane derivatives . The amide 252 could afford 4-methoxy-6-oxo-4-enenitriles 253 or seven-membered heterocycles 254a / 254b depending on the R 1 and R 2 substitutions, while the alcohol substrates 255 gave dihydropyranones 256 or oxabicyclo[4.1.0]heptanes 257 at different temperatures (Scheme ).…”

Section: Gold-catalyzed Intramolecular Reactions Of Functionalized Al...mentioning

confidence: 99%

Gold-Catalyzed Conversion of Highly Strained Compounds

et al. 2020

View full text Add to dashboard Cite

The past decade has witnessed the golden age of homogeneous gold-catalyzed reactions, especially those that involve the transformation of highly strained molecules into complex molecular architectures. Gold catalysts, with unique electronic properties and catalytic abilities, have elevated versatile reaction modes through π-interaction induced activation. On the basis of increasing research interest in this topic, together with the significant development of various ligands, including phosphine ligands and azacyclic or noncyclic carbene ligands, the understanding of the catalytic function of gold catalysts has become much deeper and more comprehensive. Different reaction needs thus could be adapted by a novel gold catalyst with a diversified ligand selection. Furthermore, the whole evolution of the gold catalysis on synthetic methodologies has realized and expanded its application into natural product synthesis as well as the potentiality of drug discovery, which endows this ancient metal with a magnificent renaissance. The reactivity of strained small ring molecules with high tension has always been an important research topic in organic chemistry. When the highly strained small ring is linked with a π-electron rich moiety or contains a heteroatom, the gold activation of the π-system or coordination with the heteroatom can initiate a cascade reaction, usually followed by ring opening or expansion. These processes can result in the rapid construction of complex and distinct molecular structures, many of which feature in biologically important molecules. In this review, we will mainly summarize the advances on diverse reaction types and molecular constructions accomplished by homogeneous gold catalysis using highly strained substrates, including methylenecyclopropanes (MCPs), vinylidenecyclopropanes (VDCPs), cyclopropenes as well as aziridine- and epoxide-containing molecules, focusing on the last 10 years. For functionalized alkynyl cyclopropanes, several early inspiring and elegant examples will be described in this review for systematically understanding these transformations.

show abstract

Gold‐Catalyzed Cycloisomerizations of Functionalyzed Cyclopropyl Alkynes: the Cases of Carboxamides and Alcohols

Cited by 16 publications

References 95 publications

Phase‐Contact Engineering in Mono‐ and Bimetallic Cu‐Ni Co‐catalysts for Hydrogen Photocatalytic Materials

Phase‐Contact Engineering in Mono‐ and Bimetallic Cu‐Ni Co‐catalysts for Hydrogen Photocatalytic Materials

CO oxidation as a test reaction for strong metal–support interaction in nanostructured Pd/FeO powder catalysts

Gold-Catalyzed Conversion of Highly Strained Compounds

Contact Info

Product

Resources

About