A mononuclear tantalum catalyst with a peroxocarbonate ligand for olefin epoxidation in compressed CO₂

Abstract

A mononuclear tantalum complex bonded to a peroxocarbonate ligand has been proved to be particularly important in the epoxidation reactions.

Designing of 3D Architecture Flower-like Mn-Promoted MgO and Its Application for CO2 Adsorption and CO2-Assisted Aerobic Oxidation of Alkylbenzenes

“…Ma et al also reported the formation of a peroxocarbonate complex for the epoxidation of olefins. Ansari et al also reported the O atom transfer from CO 2 for the oxidation of benzene to phenol. , First, the oxygen atom inserts on the surface of Mn–MgO through the oxygen vacancies and generates the phenylethyl radical . Further, the soft oxidant (CO 2 ) accommodated on Mn–MgO to form the metal­(Mn or Mg)–peroxocarbonate complex .…”

Implementing vanadium peroxides as direct air carbon capture materials

“…This is in agreement with previous reports that describe larger alkali tetraperoxovanadates (and also Mo and W counterparts) as more reactive, or even explosive. 45 That said, this faster reactivity does not necessarily translate to higher carbon capture, as revealed by characterization of the degradation products via Fourier transform infrared (FTIR), thermogravimetric analysis/ mass spectrometry (TGA-MS), powder X-ray diffraction (PXRD), 51 V solid state MAS NMR (magic angle spinning nuclear magnetic resonance) and elemental analysis, described below.…”

“…5. K 3 [VO(O 2 ) 2 CO 3 ] has a single 51 V peak at 789 ppm. The central peak was identied as the non-shiing peak upon changing spin speeds (Fig.…”

“…The formation of a peroxycarbonate ligand is the natural starting point from chemical intuition and is consistent with previous computational and experimental studies that demonstrate the ability of peroxo-containing metal species to form stable peroxycarbonate complexes. 51,52 Additionally, the transfer of an oxygen atom to form an ozone intermediate in step 3 (see Fig. S11 †) has some literature precedent in zirconium structures featuring h 2 -O 3 involved in the epoxidation of propene.…”

“…A combination of thermogravimetric analysismass spectrometry (TGA-MS), 51 V MAS NMR (magic angle spinning nuclear magnetic resonance spectrometry), quantitative carbon analysis, infrared spectroscopy (FTIR) and powder X-ray diffraction (PXRD) benchmarks the conversion of K 3 V(O 2 ) 4 immediately to K 3 VO(O 2 ) 2 (CO 3 ), and ultimately a mixture containing mostly KVO 3 plus KHCO 3 over several months. Parallel studies of the Rb and Cs analogues show the same reaction pathway, higher reactivity rates, but also a possible competing reaction of autodegradation, or water-promoted degradation.…”