406679-59-2

Upstream product

• 98-88-4 benzoyl chloride 
• 93-97-0 benzoic acid anhydride 
• 65-85-0 benzoic acid 
• 3592-47-0 Benzaldehyde-d 
• 1159923-17-7 tert-butyl 2-(2,3-dioxo-3-phenylpropanamido)acetate 
• 263273-82-1 [1,2-¹⁷O₂]benzoic acid 
• 21175-64-4 1,1-dideuteriophenylmethanol 
• 100-51-6 benzyl alcohol 
• 14915-25-4 benzyl alcohol-d 
• 4435-51-2 1-phenyl-butane-1,2,3-trione 
• 3885-45-8 ethyl 2,3-dioxo-3-phenylpropanoate 

Downstream Products

• 38612-13-4 4-bromobenzyl benzoate 
• 79825-70-0 [²H₃]methyl benzoate 

Relevant academic research and scientific papers

Solid-State 17O NMR Study of Carboxylic Acid Dimers: Simultaneously Accessing Spectral Properties of Low- And High-Energy Tautomers

We report a solid-state 17O NMR study of several crystalline carboxylic acids. We found that, while each of these compounds forms discrete hydrogen-bonded dimers in the crystal lattice, their solid-state 17O magic-angle spinning (MAS) NMR spectra display quite different features and different temperature dependencies. We showed that experimentally observed 17O NMR spectral behaviors can be explained as being due to thermal averaging between the two tautomers that are produced as a result of concerted double-hydrogen hopping dynamics within each dimer. In general, the two tautomers have different energies due to intramolecular interactions and crystal packing. From an analysis of variable-temperature 17O MAS NMR spectra, energy asymmetry between the two tautomers was experimentally determined for each of the carboxylic acid compounds studied. The same data analysis also offers an opportunity to simultaneously assess 17O NMR parameters in both low- and high-energy tautomers. We concluded that the periodic plane-wave density functional theory (DFT) calculations can produce reliable 17O NMR parameters (chemical shift and quadrupolar coupling tensors) for both tautomers. The same periodic DFT calculations have also produced reasonable energy asymmetry values for the studied carboxylic acid dimers. We have also observed substantial H/D isotope shifts in solid-state 17O NMR.

A Mononuclear Non-heme Iron(III)-Peroxo Complex with an Unprecedented High O-O Stretch and Electrophilic Reactivity

A mononuclear non-heme iron(III)-peroxo complex, [Fe(III)(O2)(13-TMC)]+ (1), was synthesized and characterized spectroscopically; the characterization with electron paramagnetic resonance, M?ssbauer, X-ray absorption, and resonance Raman spectroscopies and mass spectrometry supported a high-spin S = 5/2 Fe(III) species binding an O2 unit. A notable observation was an unusually high νO-O at ～1000 cm-1 for the peroxo ligand. With regard to reactivity, 1 showed electrophilic reactivity in H atom abstraction (HAA) and O atom transfer (OAT) reactions. In the HAT reaction, a kinetic isotope effect (KIE) value of 5.8 was obtained in the oxidation of 9,10-dihydroanthracene. In the OAT reaction, a negative ρ value of -0.61 in the Hammett plot was determined in the oxidation of p-X-substituted thioanisoles. Another interesting observation was the electrophilic reactivity of 1 in the oxidation of benzaldehyde derivatives, such as a negative ρ value of -0.77 in the Hammett plot and a KIE value of 2.2. To the best of our knowledge, the present study reports the first example of a mononuclear non-heme iron(III)-peroxo complex with an unusually high νO-O value and unprecedented electrophilic reactivity in oxidation reactions.

Tropylium-Catalyzed O-H Insertion Reactions of Diazoalkanes with Carboxylic Acids

Herein, we describe the application of a nonbenzenoid aromatic carbocation, namely tropylium, as an organic Lewis acid catalyst in O-H functionalization reactions of diazoalkanes with benzoic acids. The newly developed protocol is applicable to a wide range of diazoalkane and carboxylic acid substrates with excellent efficiency (43 examples, up to 99% yield).

Combining Structural with Functional Model Properties in Iron Synthetic Analogue Complexes for the Active Site in Rabbit Lipoxygenase

Iron complexes that model the structural and functional properties of the active iron site in rabbit lipoxygenase are described. The ligand sphere of the mononuclear pseudo-octahedral cis-(carboxylato)(hydroxo)iron(III) complex, which is completed by a tetraazamacrocyclic ligand, reproduces the first coordination shell of the active site in the enzyme. In addition, two corresponding iron(II) complexes are presented that differ in the coordination of a water molecule. In their structural and electronic properties, both the (hydroxo)iron(III) and the (aqua)iron(II) complex reflect well the only two essential states found in the enzymatic mechanism of peroxidation of polyunsaturated fatty acids. Furthermore, the ferric complex is shown to undergo hydrogen atom abstraction reactions with O-H and C-H bonds of suitable substrates, and the bond dissociation free energy of the coordinated water ligand of the ferrous complex is determined to be 72.4 kcal·mol-1. Theoretical investigations of the reactivity support a concerted proton-coupled electron transfer mechanism in close analogy to the initial step in the enzymatic mechanism. The propensity of the (hydroxo)iron(III) complex to undergo H atom abstraction reactions is the basis for its catalytic function in the aerobic peroxidation of 2,4,6-tri(tert-butyl)phenol and its role as a radical initiator in the reaction of dihydroanthracene with oxygen.

Palladium-Catalyzed Enantioselective Heteroarenyne Cycloisomerization Reaction

The extensively developed ene-type enantioselective cycloisomerization of classical 1,n-enynes provides an efficient approach to chiral cyclic 1,4-dienes. In contrast, the catalytic asymmetric heteroarenyne (heteroarene–alkyne) cycloisomerization involving the dearomative transformation of endocyclic aromatic C=C bonds remains unknown. Herein, we communicate a PdH-catalyzed enantioselective heteroarenyne cycloisomerization reaction of alkyne-tethered indole substrates (formal 1,5- and 1,6-enynes). Based on this strategy, a variety of structurally diverse chiral spiro and fused indoline derivatives bearing quaternary stereocenters and exocyclic C=C bonds are afforded in moderate to excellent yields and excellent enantioselectivities (up to 98 % ee). The classical ene-type enantioselective 1,5-enyne cycloisomerization of N-vinylpropiolamides is also developed to afford chiral 2-pyrrolones in good to excellent ee values.

METHODS FOR DEPOLYMERIZING POLYESTERS

A method for depolymerizing a polyester may comprise heating a polyester at a temperature and for a period of time in the presence of a supported metal-dioxo catalyst, optionally, in the presence of H2, to induce hydrogenolysis of ester groups in the polyester and provide monomers of the polyester.

Mechanism of the reaction of an NHC-coordinated palladium(II)-hydride with O2 in acetonitrile

PdII-hydride species are important intermediates in many Pd-catalyzed aerobic oxidation reactions, and their reaction with molecular oxygen has been the subject of considerable previous study. This investigation probes the reactivity of trans-[(IMes)2Pd(H)(OBz)] (IMes = 1,3-dimesitylimidazol-2-ylidene) with O2 in acetonitrile, a polar coordinating solvent that leads to substantial changes in the kinetic behavior of the reaction relative the previously reported reaction in benzene and other non-coordinating solvents. In acetonitrile, the benzoate ligand dissociates to form the solvent-coordinated complex trans-[(IMes)2Pd(H)(NCMe)][OBz]. Upon exposure to O2, this cationic PdII–H complex reacts to form the corresponding PdII-hydroperoxide complex trans-[(IMes)2Pd(OOH)(NCCD3)][OBz]. Kinetic studies of this reaction revealed a complex rate law, rate = k1k2[3][OBz]/(k?1[CD3CN] + k2[OBz]) + k3[3][OBz], which is rationalized by a mechanism involving two parallel pathways for rate-limiting deprotonation of the PdII–H species to generate the Pd0 complex, Pd(IMes)2. The latter complex undergoes rapid (kinetically invisible) reaction with O2 and BzOH to afford the PdII-hydroperoxide product. The results of this study are compared to observations from the previously reported reaction in benzene and discussed in the context of catalytic reactivity.

Polyethylene Terephthalate Deconstruction Catalyzed by a Carbon-Supported Single-Site Molybdenum-Dioxo Complex

Polyethylene terephthalate (PET) is selectively depolymerized by a carbon-supported single-site molybdenum-dioxo catalyst to terephthalic acid (PTA) and ethylene. The solventless reactions are most efficient under 1 atmosphere of H2. The catalyst exhibits high stability and can be recycled multiple times without loss of activity. Waste beverage bottle PET or a PET + polypropylene (PP) mixture (simulating the bottle + cap) proceeds at 260 °C with complete PET deconstruction and quantitative PTA isolation. Mechanistic studies with a model diester, 1,2-ethanediol dibenzoate, suggest the reaction proceeds by initial retro-hydroalkoxylation/β-C?O scission and subsequent hydrogenolysis of the vinyl benzoate intermediate.

Highly efficient oxidation of alcohols to carboxylic acids using a polyoxometalate-supported chromium(iii) catalyst and CO2

Direct catalytic oxidation of alcohols to carboxylic acids is very attractive, but economical catalysis systems have not yet been well established. Here, we show that a pure inorganic ligand-supported chromium compound, (NH4)3[CrMo6O18(OH)6] (simplified as CrMo6), could be used to effectively promote this type of reaction in the presence of CO2. In almost all cases, oxidation of various alcohols (aromatic and aliphatic) could be achieved under mild conditions, and the corresponding carboxylic acids can be achieved in high yield. The chromium catalyst 1 can be reused several times with little loss of activity. Mechanism study and control reactions demonstrate that the acidification proceeds via the key oxidative immediate of aldehydes.

Isotope Labeling Reveals Fast Atomic and Molecular Exchange in Mechanochemical Milling Reactions

Using tandem in situ monitoring and isotope-labeled solids, we reveal that mechanochemical ball-milling overcomes inherently slow solid-state diffusion through continuous comminution and growth of milled particles. This process occurs with or without a ne