Mechanical recycling of plastic waste is not sustainable and inefficient in terms the resources needed to accomplish process, quality materials obtained from this technique substandard. Chemical polymers appears be preferable because technology allows for production new materials. This review compiles most recent research which selected transition metals are used as catalysts hydrogenolytic depolymerization polyolefins a polymer upcycling process. Hydrogenolysis an emerging chemical method...

New porous organic polymers have been synthesized and applied as catalysts for cycloaddition of CO₂and epoxides under mild conditions with excellent recyclability.

Two new trans- and cis-[(NHC)(2)PdX(2)] (X=Cl, Br) complexes of N/O-functionalized N-heterocyclic carbenes employed in a highly convenient amine-free Sonogashira cross-coupling reaction air polar mixed aqueous medium are reported. Specifically, the trans-[{1-benzyl-3-(3,3-dimethyl-2-oxobutyl)imidazol-2-ylidene}(2)PdBr(2)] (3) cis-[{1-benzyl-3-(N-tert-butylacetamido)imidazol-2-ylidene}(2)PdCl(2)] (4) effectively catalyzed aryl iodides with substituted acetylenes solvent (DMF/H(2)O, 3:1 v/v)...

We report a novel luminescent Al-based metal-organic gel G1 comprising 1,4,5,8-triptycenetetracarboxylic acid, which exhibits highly sensitive detection towards nitro aromatic compounds particularly picric acid. Furthermore, under identical reaction conditions, using Co(II) salt instead, 3D framework material, trip-MOF-1, was isolated and its sensitivity acid also evaluated.

We report here an accurate surface organometallic chemistry (SOMC) approach to propane oxidative dehydrogenation (ODH) using a μ2-oxo-bridged, bimetallic [V2O4(acac)2] (1) (acac = acetylacetonate anion) complex as precursor. The identity and the nuclearity of product grafting subsequent treatment have been systematically studied by means FT-IR, Raman, solid-state (SS) NMR, UV–vis DRS, EPR EXAFS spectroscopies. show that 1 on silica under rigorous SOMC protocol thermal lead exclusively...

Single-site yttrium complexes were prepared by immobilization of an intermediate cycloaddition CO₂ to epoxides and applied in catalysis.

The well-defined silica-supported molybdenum oxo alkyl species (≡SiO-)MoO(CH2tBu)3 was selectively prepared by grafting of MoO(CH2tBu)3Cl onto partially dehydroxylated silica (silica700) using the surface organometallic chemistry approach. This fully characterized elemental analysis and DRIFT, solid-state NMR, EXAFS spectroscopy. new material is related to active industrial supported MoO3/SiO2 olefin metathesis catalysts. It displays very high activity in propene self-metathesis at mild...

Accessing highly electron deficient partially alkylated tungsten hydrides on silica <italic>via</italic> controlled hydrogenolysis of surface organometallic complex (Si–O–)W(Me)₅.

Two Zn MOFs, MOF-645 and MOF-646, comprised of polarized 1,3-azulenedicarboxylate were synthesized. The guest free MOF-646 showed strong MOF-H2 interactions (7.8–6.8 kJ mol−1), which revealed the significant impact internally azulene backbone to stabilized H2 molecules in framework.

A well-defined silica-supported monoalkylated tungsten dioxo complex [(≡Si–O−)W(═O)2(CH2–tBu)] was prepared by treatment of highly dehydroxylated silica (SiO2-700: treated at 700 °C under high vacuum) with an ionic precursor [NEt4][W(═O)3(CH2–tBu)]. The identity the resulting neutral surface established means elemental microanalysis and spectroscopic studies (IR, solid-state NMR, Raman, X-ray absorption spectroscopies). supported found to act as a precatalyst for self-metathesis 1-octene in...

Abstract Catalytic glycolysis of polyethylene terephthalate (PET) into its monomer, bis(2‐hydroxyethyl) (BHET), is a major focus chemical research in recent decades. Metal catalysts, especially heavy metal salts, are recognized for their efficiency degrading this widely used thermoplastic. However, concerns over the non‐biodegradable and toxic nature catalysts like Zn Pb along with limited selectivity, have led researchers to seek alternative, more environmentally friendly, cost‐effective...

Novel PNP ligands bearing an N-triptycene backbone were developed and evaluated for selective ethylene oligomerization. Upon activation with MMAO-3A, the pre-catalyst mixture containing Cr(acac)3/ligand efficiently promotes tetramerization remarkably high productivities (up to 1733 kg gCr-1 h-1) C8 olefin selectivities 74.1 wt%). More importantly, a moiety connecting at 1- or 1,4-position of triptycene molecule could achieve exceptionally alpha (1-C6 + 1-C8) selectivities, exceeding 90 wt%,...

Two novel 3D MOFs, namely MOF-647A and MOF-648 (previously unknown trinodal 4-connected net), comprised of Cu ions pyrazole-3,5-dicarboxylate were synthesized characterized. A strategy for incorporating open metal sites in MOFs was investigated by utilizing an situ generated metal–linker complex as a precursor to construct MOF-648.

To improve the binding energy of hydrogen, incorporation internally polarized organic units into metal–organic frameworks (MOFs) should be a promising strategy. In this study, two novel MOFs composed 2,6-azulenedicarboxylate (2,6-azd), termed MOF-649 [Zn2(2,6-azd)2(dabco), where dabco = 1,4-diazabicyclo[2.2.2]octane] and MOF-650 [Zn4O(2,6-azd)3], have been synthesized, their crystal structures were determined by single-crystal X-ray diffraction analyses. Both materials displayed permanent...

Tetramerization of ethylene by chromium catalysts stabilized with functionalized N-aryl phosphineamine ligands C6H4(m-CF3)N(PPh2)2 (1), C6H4(p-CF3)N(PPh2)2 (2), C6H4(o-CF3)N=PPh2-PPh2 (3), and C6H3(3,5-bis(CF3))N(PPh2)2 (4) was evaluated. The parameter optimization includes temperature, co-catalyst, solvent. Upon activation MMAO-3A, the new catalyst system especially m-functional PNP ligand (1) exhibited high 1-octene selectivity productivity while giving minimum undesirable polyethylene...

Synthesis, structure, and olefin metathesis activity of a surface complex [(≡Si-O-)W(═O)(CH3)2-ImDippN] (4) (ImDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato) supported on silica by organometallic chemistry (SOMC) approach are reported. The reaction N-silylated 2-iminoimidazoline with tungsten(VI) oxytetrachloride generated the tungsten oxo imidazolin-2-iminato chloride [ImDippNW(═O)Cl3] (2). This was grafted partially dehydroxylated pretreated at 700 °C (SiO2-700) to afford...

The catalytic oxidation of cis-2-butene and propylene with molecular oxygen in the presence a well-defined surface coordination compound, (≡SiO)2Mo(═O)2, affords acetaldehyde. Using cis-2-butene/O2 feed at 350–400 °C, reaction yields conversion approximately 10% an acetaldehyde selectivity 70%. This performance is maintained up to experimental time 20 h continuous flow reactor. Mo(bis-oxo) compound was fully characterized by multiple spectroscopic techniques as well microanalysis. results...

Fly ash (FA)-supported bimetallic nanoparticles (PdxAgy/FA) with varying Pd:Ag ratios were prepared by coprecipitation of Pd and Ag involving in situ reduction Pd(II) Ag(I) salts aqueous medium. All the supported thoroughly characterized aid powder X-ray diffraction (PXRD), photoelectron spectroscopy (XPS), electron microscopy (field emission scanning (FE-SEM) transmission (TEM)), elemental analyses, which include inductively coupled plasma-optical (ICP-OES) energy-dispersive (EDS). A...

The well-defined single-site silica-supported hafniaaziridine complex [(≡Si–O−)Hf(η2,π-MeNCH2)(η1-NMe2)(η1-HNMe2)] was prepared using surface organometallic chemistry. Upon thermal treatment under high vacuum, the grafted species converted into unprecedented hafnium imido bis-amido [(≡Si–O−)Hf(═NMe)(η1-NMe2)]. complexes were characterized by elemental analysis and following spectroscopic techniques: infrared, solid-state single multiple quantum NMR, advanced DNP-SENS, extended X-ray...

A chlorination method for the selective substitution of well-defined isolated silanol groups silica surface has been developed using catalytic Appel reaction. Spectroscopic analysis, complemented by elemental microanalysis studies, reveals that a quantitative could be achieved with highly dehydroxylated materials exclusively possess non-hydrogen bonded groups. The employed did not leave any carbon or phosphorus residue on and can regarded as promising tool future functionalization metal...

Selective hydroamination of terminal alkynes with primary aryl amines is catalyzed by an unprecedented well-defined silica-supported tantalum complex [(≡Si–O−)Ta(η1σ-NEtMe)2(=NtBu)]. A molecular-level characterization the surface organometallic Ta species was done help techniques including in situ infrared, 1H and 13C solid-state NMR (including double triple quanta sequencing), X-ray absorption spectroscopies. These were complemented state-of-the-art DNP-SENS 15N characterization. Several...

Novel site-isolated tetracoordinated molybdenum complexes possessing bis(imido) ligands, [(≡Si–O)2Mo(═NR)2] (R = t-Bu, 2,6-C6H3-i-Pr2), were immobilized on partially dehydroxylated silica (SiO2-200) by a rigorous surface organometallic chemistry protocol. The newly developed materials adorned with functional units, which previously exploited mainly as spectator ligands silica-supported olefin metathesis catalysts, are found to be efficient heterogeneous catalytic systems for imine cross...