611-63-2

Upstream product

• 75802-19-6 1-Ethoxy-1,3-dihydroisobenzofuran 
• 614-45-9 tert-Butyl peroxybenzoate 
• 613-31-0 9,10-dihydroanthracene 
• 18370-16-6 9-acetoxy-9,10-dihydroanthracene 

Downstream Products

• 120-12-7 anthracene 
• 78299-03-3 9-Methoxy-9,10-dihydro-anthracene 
• 82247-13-0 10-[1-(4-Hydroxy-3-methoxy-phenyl)-2-(2-methoxy-phenoxy)-ethyl]-10H-anthracen-9-one 
• 82247-17-4 threo-1-(3-methoxy-4-hydroxyphenyl)-1-(9-oxoanthracen-10-yl)-2-(2-methoxyphenoxy)propan-3-ol 
• 613-31-0 9,10-dihydroanthracene 
• 2141-42-6 1,2,3,4-tetrahydroanthracene 
• 7732-18-5 water 
• 14314-91-1 9-H-anthracenonium ion 
• 90-44-8 anthracen-9(10H)-one 
• 84-65-1 9,10-phenanthrenequinone 
• 523-27-3 9,10-Dibromoanthracene 

Relevant academic research and scientific papers

Fabrication of CuCr2O4 spinel nanoparticles: A potential catalyst for the selective oxidation of cycloalkanes via activation of Csp3-H bond

We report here preparation of CuCr2O4 spinel nanoparticle catalyst, mediated by cationic surfactant CTAB in hydrothermal route. XRD revealed the formation of CuCr2O4 spinel phase and TEM showed the particle size of 30-60 nm. The catalyst was speculated to be highly active for selective oxidation of cyclohexane to cyclohexanone with H2O2. A cyclohexane conversion of 70% with 85% cyclohexanone selectivity was achieved over this catalyst at 50 °C temperature. Moreover, the catalyst did not show any significant activity loss even after 8 reuses and proved its efficacy in the oxidation of other cycloalkanes also.

Combined experimental and theoretical study on the reactivity of Compounds I and II in horseradish peroxidase biomimetics

For the exploration of the intrinsic reactivity of two key active species in the catalytic cycle of horseradish peroxidase (HRP), Compound I (HRP-I) and Compound II (HRP-II), we generated in situ [FeIV=O(TMP+?)(2-MeIm)] + and [FeIV=O(TMP)(2-MeIm)]0 (TMP = 5,10,15,20-tetramesitylporphyrin; 2-MeIm = 2-methylimidazole) as biomimetics for HRP-I and HRP-II, respectively. Their catalytic activities in epoxidation, hydrogen abstraction, and heteroatom oxidation reactions were studied in acetonitrile at -15 °C by utilizing rapid-scan UV/Vis spectroscopy. Comparison of the secondorder rate constants measured for the direct reactions of the HRP-I and HRP-II mimics with the selected substrates clearly confirmed the outstanding oxidizing capability of the HRP-I mimic, which is significantly higher than that of HRP-II. The experimental study was supported by computational modeling (DFT calculations) of the oxidation mechanism of the selected substrates with the involvement of quartet and doublet HRP-I mimics (2,4Cpd I) and the closed-shell triplet spin HRP-II model (3Cpd II) as oxidizing species. The significantly lower activation barriers calculated for the oxidation systems involving 2,4Cpd I than those found for 3Cpd II are in line with the much higher oxidizing efficiency of the HRP-I mimic proven in the experimental part of the study. In addition, the DFT calculations show that all three reaction types catalyzed by HRP-I occur on the doublet spin surface in an effectively concerted manner, whereas these reactions may proceed in a stepwise mechanism with the HRP-II mimic as oxidant. However, the high desaturation or oxygen rebound barriers during C-H bond activation processes by the HRP-II mimic predict a sufficient lifetime for the substrate radical formed through hydrogen abstraction. Thus, the theoretical calculations suggest that the dissociation of the substrate radical may be a more favorable pathway than desaturation or oxygen rebound processes. Importantly, depending on the electronic nature of the oxidizing species, that is, 2,4Cpd I or 3Cpd II, an interesting region-selective conversion phenomenon between sulfoxidation and H-atom abstraction was revealed in the course of the oxidation reaction of dimethylsulfide. The combined experimental and theoretical study on the elucidation of the intrinsic reactivity patterns of the HRP-I and HRP-II mimics provides a valuable tool for evaluating the particular role of the HRP active species in biological systems.

Copper-catalyzed benzylic oxidation of C(sp3)-H bonds

A selective oxidation of benzylic C(sp3)-H bonds to C(sp 3)-O bonds catalyzed by copper complexes of quinoline-imine ligands was developed with peresters as oxidants under mild reaction conditions, which converted benzylic methylenes directly into benzylic alcohols and esters by means of direct C-H bond functionalization.

Comparison of pKR values of fluorenyl and anthracenyl cations

A value of pKR = -5.1 for the anthracenonium ion in 50:50 (v/v) aqueous trifluorethanol is reported based on a ratio of measured rate constants kH for acid-catalysed dehydration of the 9,10-hydrate of anthracene and kH2O for the reverse hydrolysis of the carbocation (KR = kH2O/kH. Comparison with pKR = -15.9 for the fluorenyl cation indicates that the latter ion is less stable by more than 10 log units (15 kcal mol-1). This difference is (a) considerably larger than that between the benzhydryl (pKR = -11.7) and fluorenyl cations (ΔpK = 4.2), which has been considered too small to indicate antiaromatic character for the fluorenyl cation, and (b) comparable to that between pKas for the ionization (in DMSO) of fluorene (22.6) and diphenylmethane (32.2), which has been interpreted as implying aromatic character for the fluorenyl anion. It is shown that a difference in stability of anthracene hydrate and 9-hydroxyfluorene makes only a minor contribution to the difference in pKR values and that the fluorenyl cation is destabilized by ca 10 kcal mol-1. A smaller difference in pKas for protonation of fluorenimine (5.85) and benzhydrylimine (7.0) is consistent with the expected moderating effect of an electron-donating substituent on relative carbocation stabilities. Evidence from calculations relating to the antiaromaticity of the fluorenyl cation is reviewed in the light of these measurements. An additional comparison between equilibrium constants for the ionization of aralkylazides (Kaz) and alcohols (KR) reveals the influence of differences in geminal σ-bond interactions for the hydroxy and azido groups in their respective reactants. Copyright

Protonated benzofuran, anthracene, naphthalene, benzene, ethene, and ethyne: Measurements and estimates of pKa and pKR

Aqueous solvolyses of acyl derivatives of hydrates (water adducts) of anthracene and benzofuran yield carbocations which undergo competitive deprotonation to form the aromatic molecules and nucleophilic reaction with water to give the aromatic hydrates. Trapping experiments with azide ions yield rate constants kp for the deprotonation and kH2O for the nucleophilic reaction based on the azide clock . Combining these with rate constants for (a) the H+-catalyzed reaction of the hydrate to form the carbocation and (b) hydrogen isotope exchange of the aromatic molecule (from the literature) yields pKR = -6.0 and -9.4 and pKa = -13.5 and -16.3 for the protonated anthracene and protonated benzofuran, respectively. These pK values may be compared with pKR = -6.7 for naphthalene hydrate (1-hydroxy-1,2-dihydronaphthalene), extrapolated to water from measurements by Pirinccioglu and Thibblin for acetonitrile-water mixtures, and pKa = -20.4 for the 2-protonated naphthalene from combining kp with an exchange rate constant. The differences between pKR and pKa correspond to pKH2O, the equilibrium constant for hydration of the aromatic molecule (pKH2O = pKR - pka). For naphthalene and anthracene values of pKH2O = +13.7 and +7.5 compare with independent estimates of +14.2 and +7.4. For benzene, pKa = -24.3 is derived from an exchange rate constant and an assigned value for the reverse rate constant close to the limit for solvent relaxation. Combining this pKa with calculated values of pKH2O gives pKR = -2.4 and -2.1 for protonated benzenes forming 1,2- and 1,4-hydrates, respectively. Coincidentally, the rate constant for protonation of benzene is similar to those for protonation of ethylene and acetylene (Lucchini, V.; Modena, G. J. Am. Chem Soc. 1990, 112, 6291). Values of pKa for the ethyl and vinyl cations (-24.8) may thus be derived in the same way as that for the benzenonium ion. Combining these with appropriate values of pKH2O then yields pKR = -39.8 and -29.6 for the vinyl and ethyl cations, respectively.

Preparation of Isobenzofuran-Aryne Cycloadducts

A one-pot procedure is described for carrying out the sequence 1,4-elimination of acetal 1 to form isobenzofuran; the formation of 1,3-dilithioisobenzofuran; the conversion to 1,3-bis(trimethylsilyl)isobenzofuran (5); the generation of arynes and cycloaddition to 5.This method allows the use of lithium tetramethylpiperidide induced dehydrohalogenation of haloaromatics to generate the arynes, a procedure which fails with unsilylated isobenzofuran due to the acidity of the 1,3-protons.The protiodesilylation of the cycloadducts occurs with surprising ease, upon treatmentwith either tetraalkylammonium fluoride/THF or base (potassium tert-butoxide or KOH) in Me2SO, to furnish the novel unsubstituted isobenzofuran-aryne adducts.Three examples are given, utilizing benzyne, 1-naphthalyne, and 3-pyridine.Procedures for subsequent deoxygenation of the cycloadducts to anthracene, benzanthracene, and benzisoquinoline, respectively, are described.The cycloadduct precursor of benzanthracene is shown to undergo highly regioselective reduction on treatment with lithium tri-tert-butoxyaluminohydride/triethylborane, with preferential attack occurring at the more accessible 7-position.