Heterogeneous Catalyst for the Selective Oxidation of Unactivated Hydrocarbons Based on a Tethered Metal-Coordinated Cavitand

Abstract

A new selective hydrocarbon oxidation heterogeneous catalyst has been developed by tethering an iron-coordinated cavitand to the surfaces of a SBA-15 mesoporous material. The resulting material was shown to catalyze the oxidation of cyclic hydrocarbons at room temperature and to be quite robust and easily recyclable. The role of the cavitand scaffold is to prevent the catalytic Fe ions from interacting directly with the silica surface and to provide a controlled environment for reversible redox catalysis. An induction period is required for the activation of the catalyst, during which a change in coordination of the iron ions to the tethered cavitand takes place.

Correlated bifunctionality in heterogeneous catalysts: selective tethering of cinchonidine next to supported Pt nanoparticles

“…41,45,46 All data correspond to averages of 1024 scans, taken at 4 cm −1 resolution and ratioed against an appropriate reference spectrum. Solid-state 13 C cross polarization magic angle spinning (CP-MAS) NMR spectra were acquired using a Bruker Avance 600 spectrometer, with the CP-MAS probe operating at 119.2 MHz, a cross-polarization contact time of 2 ms, a 1 H decoupling bandwidth of 80 kHz, and a recycle time of 3 s. 47 Data were acquired as 12 000 coadded 2048 complex data point FIDs with a sweep width of 100 kHz. Post-acquisition processing consisted of exponential multiplication with 200 Hz of line broadening and zero filling to 4096 data points.…”

Vapor phase condensation of methyl acetate with formaldehyde to preparing methyl acrylate over cesium supported SBA-15 catalyst

“…The esterification of acrylic acid with 23 methanol then leads to methyl acrylate. 24 The raw materials for these processes are mostly based on 25 petroleum. Due to the depletion of restricted fossil oil stocks and 26 the increase in the price of petroleum, attention has recently been 27 paid to the products of coal chemicals [9] (methanol) and its 28 downstream products, such as methyl acetate and formaldehyde.…”

“…Pure silica zeolites SBA-15 are 52 used in the catalytic reaction, and consist of a hexagonally ordered 53 mesoporous substance that possesses a large pore size, thick pore 54 walls, and high hydrothermal stability, and is modified with alkali 55 metals or transition metals to become the base catalyst [22][23][24]. 56…”

Stereoselective Alkane Oxidation with meta-Chloroperoxybenzoic Acid (MCPBA) Catalyzed by Organometallic Cobalt Complexes

“…In many cases, oxidation leads to the formation of three main products (alkyl hydroperoxide, alcohol and ketone). If a reaction solution is injected directly (see, for example, [57,58,59,60,61,62]) to the chromatograph, the alkyl hydroperoxide ROOH (if present) decomposes in the injector and/or column to produce the alcohol and ketone in approximately equal amounts.…”