- Experimental and Theoretical Studies on Gas-Phase Fragmentation Reactions of Protonated Methyl Benzoate: Concomitant Neutral Eliminations of Benzene, Carbon Dioxide, and Methanol
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Protonated methyl benzoate, upon activation, fragments by three distinct pathways. The m/z 137 ion for the protonated species generated by helium-plasma ionization (HePI) was mass-selected and subjected to collisional activation. In one fragmentation path
- Xia, Hanxue,Zhang, Yong,Attygalle, Athula B.
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Read Online
- Zinc bromide promoted coupling of isonitriles with carboxylic acids to form 2,4,5-trisubstituted oxazoles
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Deviant behavior: In a deviation from "normal" reactivity, isocyanides underwent co-trimerization with carboxylic acids in the presence of ZnBr2 to smoothly provide oxazoles (see scheme). The reaction is thought to occur by initial nucleophilic
- Odabachian, Yann,Tong, Shuo,Wang, Qian,Wang, Mei-Xiang,Zhu, Jieping
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- Phosphorus-Based Organocatalysis for the Dehydrative Cyclization of N-(2-Hydroxyethyl)amides into 2-Oxazolines
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A metal-free, biomimetic catalytic protocol for the cyclization of N-(2-hydroxyethyl)amides to the corresponding 2-oxazolines (4,5-dihydrooxazoles), promoted by the 1,3,5,2,4,6-triazatriphosphorine (TAP)-derived organocatalyst tris(o-phenylenedioxy)cyclotriphosphazene (TAP-1) has been developed. This approach requires less precatalyst compared to the reported relevant systems, with respect to the phosphorus atom (the maximum turnover number (TON) ~30), and exhibits a broader substrate scope and higher functional-group tolerance, providing the functionalized 2-oxazolines with retention of the configuration at the C(4) stereogenic center of the 2-oxazolines. Widely accessible β-amino alcohols can be used in this approach, and the cyclization of N-(2-hydroxyethyl)amides provides the desired 2-oxazolines in up to 99% yield. The mechanism of the reaction was studied by monitoring the reaction using spectral and analytical methods, whereby an 18O-labeling experiment furnished valuable insights. The initial step involves a stoichiometric reaction between the substrate and TAP-1, which leads to the in situ generation of the catalyst, a catechol cyclic phosphate, as well as to a pyrocatechol phosphate and two possible active intermediates. The dehydrative cyclization was also successfully conducted on the gram scale.
- Soleymani Movahed, Farzaneh,Foo, Siong Wan,Mori, Shogo,Ogawa, Saeko,Saito, Susumu
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supporting information
p. 243 - 257
(2021/12/17)
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- 18O-Labeled chiral compounds enable the facile determination of enantioselectivity by mass spectroscopy
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The synthesis of 18O-labeled enantioenriched compounds and their facile evaluation system to determine enantiomeric excess (ee) using mass spectroscopy was described. Equimolar mixture of 18O-labeled and non-labeled pseudo-enantiomers were used as a substrate for enzyme-catalyzed kinetic resolution. Ees determined by mass spectroscopy showed good agreement with those by HPLC. Our method would be a promising tool for fast evaluation of ee and contribute to development of enantioselective transformations.
- Mandai, Kyoko,Tsuchihashi, Yuta,Ashikari, Yosuke,Yoshida, Jun-ichi,Nagaki, Aiichiro
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supporting information
(2019/12/24)
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- Selective C-C bond cleavage of amides fused to 8-aminoquinoline controlled by a catalyst and an oxidant
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Herein, copper-catalyzed direct C-C bond cleavage of amides fused to 8-aminoquinoline as a directing group to form urea in the presence of amines and dioxygen is reported. Compared to the previous C-H aminations of amides via C-H activation, this reaction presents a catalyst and oxidant controlled C-C bond cleavage strategy that enables amidation through a radical process. CuBr/Ag2CO3/O2 shows the best catalytic result at 150 °C. A series of aryl and alkyl amides were compatible with this transformation. Notably, this method provided access to cyclohexanone, one of the most important industrial materials. The pathway of this reaction was investigated.
- Li, Sen,Jie, Kun,Yan, Wenjie,Pan, Qingjun,Zhang, Min,Wang, Yufeng,Fu, Zhengjiang,Guo, Shengmei,Cai, Hu
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supporting information
p. 13820 - 13823
(2020/11/18)
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- Transformations of N-arylpropiolamides to indoline-2,3-diones and acids via C≡C triple bond oxidative cleavage and C(sp2)–H functionalization
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A new palladium-catalyzed oxidative conversion of N-arylpropiolamides and H2O to various indoline-2,3-diones and acids through the C≡C triple bond cleavage and C(sp2)–H functionalization is described, which is promoted by a cooperative action of catalytic CuBr2, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and O2. The method provides a practical tool for transformations of alkynes by means of a C–H functionalization strategy, which enables the formation of one C–C bond and multiple C–O bonds in a single reaction with high substrates compatibility and excellent functional group tolerance.
- Zhou, Ming-Bo,Li, Yang,Ouyang, Xuan-Hui,Li, Jin-Heng
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p. 222 - 227
(2019/11/13)
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- Copper-catalyzed oxidative cleavage of Passerini and Ugi adducts in basic medium yielding α-ketoamides
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The aerobic oxidative cleavage of Passerini and Ugi adducts in the presence of base and copper(i) iodide is studied in detail. The oxidative cleavage yields α-ketoamides along with acids and amides from Passerini and Ugi adducts respectively. Mechanistic investigations revealed that the reaction proceeds via a radical pathway involving molecular oxygen. Control experiments with 18O-labeled Passerini adducts confirmed that molecular oxygen is the source of oxygen in α-ketoamides. A variety of Passerini and Ugi adducts were studied to explore the effect of substitution. Overall, the present study provides an insight into the reactivity of Passerini and Ugi adducts in strong basic conditions along with a method to prepare α-ketoamides.
- Ghoshal, Anirban,Ambule, Mayur D.,Sravanthi, Revoju,Taneja, Mohit,Srivastava, Ajay Kumar
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supporting information
p. 14459 - 14474
(2019/10/01)
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- Rhodium-Catalyzed Formal C-O Insertion in Carbene/Alkyne Metathesis Reactions: Synthesis of 3-Substituted 3 H-Indol-3-ols
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An efficient and novel rhodium-catalyzed formal C-O insertion reaction of alkyne-tethered diazo compounds for the synthesis of 3H-indol-3-ols is described. A type of donor/donor rhodium carbene generated in situ via a carbene/alkyne metathesis (CAM) proce
- Jia, Shikun,Dong, Guizhi,Ao, Chaoqun,Jiang, Xianxing,Hu, Wenhao
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supporting information
p. 4322 - 4326
(2019/06/17)
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- Nitrogen Dioxide Catalyzed Aerobic Oxidative Cleavage of C(OH)–C Bonds of Secondary Alcohols to Produce Acids
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Stable organic nitroxyl radicals are an important class of catalysts for oxidation reactions, but their wide applications are hindered by their steric hinderance, high cost, complex operation, and separation procedures. Herein, NO2 in DMSO is shown to effectively catalyze the aerobic oxidative cleavage of C(OH)?C bonds to form a carboxylic group, and NO2 was generated in situ by decomposition of nitrates. A diverse range of secondary alcohols were selectively converted into acids in excellent yields in this transition-metal-free system without any additives. Preliminary results also indicate its applicability to depolymerize recalcitrant macromolecular lignin. Detail studies revealed that NO2 from nitrates promoted the reaction, and NO2 served as hydrogen acceptor and radical initiator for the tandem oxidative reaction.
- Liu, Mingyang,Zhang, Zhanrong,Song, Jinliang,Liu, Shuaishuai,Liu, Huizhen,Han, Buxing
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supporting information
p. 17393 - 17398
(2019/11/11)
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- Silver(I)-Catalyzed Widely Applicable Aerobic 1,2-Diol Oxidative Cleavage
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The oxidative cleavage of 1,2-diols is a fundamental organic transformation. The stoichiometric oxidants that are still predominantly used for such oxidative cleavage, such as H5IO6, Pb(OAc)4, and KMnO4, generate stoichiometric hazardous waste. Herein, we describe a widely applicable and highly selective silver(I)-catalyzed oxidative cleavage of 1,2-diols that consumes atmospheric oxygen as the sole oxidant, thus serving as a potentially greener alternative to the classical transformations.
- Zhou, Zhong-Zhen,Liu, Mingxin,Lv, Leiyang,Li, Chao-Jun
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supporting information
p. 2616 - 2620
(2018/02/13)
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- A Three-Component Enantioselective Cyclization Reaction Catalyzed by an Unnatural Amino Acid Derivative
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A new diastereo- and enantioselective three-component cyclization reaction is described. The reaction takes place between a ketone, a carboxylic acid, and a nitroalkene to yield a bicyclic octahydro-2H-indol-2-one scaffold possessing three chiral centers. This reaction involves a rearrangement of the nitro group under simple thermal conditions. A plausible mechanism is proposed for this new reaction based on DFT calculations and isotope-labeling experiments. A new concise enantioselective synthesis of the alkaloid (+)-pancracine is presented as an example of the potential of this novel organocatalytic cyclization reaction in the synthesis of natural products.
- de Gracia Retamosa, María,Ruiz-Olalla, Andrea,Bello, Tamara,de Cózar, Abel,Cossío, Fernando P.
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supporting information
p. 668 - 672
(2018/01/17)
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- Mechanism of Acylative Oxidation-Reduction-Condensation Reactions Using Benzoisothiazolones as Oxidant and Triethylphosphite as Stoichiometric Reductant
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We previously described a new organocatalytic oxidation-reduction-condensation for amide/peptide construction. The reaction system relies on triethylphosphite as the stoichiometric reductant and organocatalytic benzoisothiazolone/O2 in air as the oxidant. The reaction was assumed to generate catalytic quantities of S-acylthiosalicylamides as electrophiles, which are rapidly intercepted by amine reactants to generate amides/peptides and o-mercaptobenzamides. The latter are then gently reoxidized to the benzoisothiazolones under Cu-catalyzed aerobic conditions to complete the catalytic cycle. To gain a mechanistic understanding, we describe herein our studies of the stoichiometric generation of S-acylthiosalicylamides under oxidation-reduction-condensation conditions from a variety of benzoisothiazolones and carboxylic acids using triethylphosphite as the terminal reductant. These studies have revealed the presence of more than one reaction pathway when benzoisothiazolones react with triethylphosphite (including a rapid, direct deoxygenation of certain classes of benzoisothiazolones by triethylphosphite) and allow the identification of optimal reaction characteristics (benzoisothiazolone structure and solvent) for the generation of thioesters. These explorations will inform our efforts to develop highly effective and robust organocatalytic oxidation-reduction-condensation reactions that are based on the benzoisothiazolone and related motifs.
- Gangireddy, Pavankumar,Patro, Vidyavathi,Lam, Leighann,Morimoto, Mariko,Liebeskind, Lanny S.
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p. 3513 - 3529
(2017/04/11)
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- Conversion of nitroalkanes into carboxylic acids via iodide catalysis in water
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We report a new method for the conversion of nitroalkanes into carboxylic acids that achieves this transformation under very mild conditions. Catalytic amounts of iodide in combination with a simple zinc catalyst are needed to give good conversions into the corresponding carboxylic acids.
- Marcé, Patricia,Lynch, James,Blacker, A. John,Williams, Jonathan M. J.
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p. 1013 - 1016
(2016/01/16)
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- Aerobic Copper-Catalyzed O-Methylation with Methylboronic Acid
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The oxidative coupling of alkylboronic acids with oxygen nucleophiles offers a strategy for replacing toxic, electrophilic alkylating reagents. Although the Chan-Lam reaction has been widely applied in the arylation of heteroatom nucleophiles, O-alkylation with boronic acids is rare. We report a Cu-catalyzed nondecarboxylative methylation of carboxylic acids with methylboronic acid that proceeds in air with no additional oxidant. An isotope-labeling study supports an oxidative cross-coupling mechanism, in analogy to that proposed for Chan-Lam arylation.
- Jacobson, Clare E.,Martinez-Mu?oz, Noelia,Gorin, David J.
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p. 7305 - 7310
(2015/07/28)
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- O-Transfer-facilitated cyclizations of propargylamides with TMSN3: Selective synthesis of tetrazoles and dihydroimidazoles
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An unprecedented formal [3+2] annulation of propargylamides with TMSN3 to deliver functionalized tetrazoles is developed. Oxygen-atom transfer (OAT) from the amide group to the CC bond was realized via a NIS-triggered-cyclization/ring-opening cascade pathway. The OAT process enables the amide to serve as a two-atom unit in the reactions. Notably, in situ umpolung of azide occurred when terminal propargylamides were employed in this reaction, providing an array of diiodomethylated dihydroimidazoles.
- Hu, Yancheng,Yi, Ruxia,Yu, Xinzhang,Xin, Xiaoyi,Wang, Chunxiang,Wan, Boshun
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supporting information
p. 15398 - 15401
(2015/10/20)
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- Halide-promoted dioxygenolysis of a carbon-carbon bond by a copper(II) diketonate complex
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A mononuclear Cu(II) chlorodiketonate complex was prepared, characterized, and found to undergo oxidative aliphatic carbon-carbon bond cleavage within the diketonate unit upon exposure to O2 at ambient temperature. Mechanistic studies provide evidence for a dioxygenase-type C-C bond cleavage reaction pathway involving trione and hypochlorite intermediates. Significantly, the presence of a catalytic amount of chloride ion accelerates the oxygen activation step via the formation of a Cu-Cl species, which facilitates monodentate diketonate formation and lowers the barrier for O2 activation. The observed reactivity and chloride catalysis is relevant to Cu(II) halide-catalyzed reactions in which diketonates are oxidatively cleaved using O2 as the terminal oxidant. The results of this study suggest that anion coordination can play a significant role in influencing copper-mediated oxygen activation in such systems.
- Allpress, Caleb J.,Mi?aczewska, Anna,Borowski, Tomasz,Bennett, Jami R.,Tierney, David L.,Arif, Atta M.,Berreau, Lisa M.
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supporting information
p. 7821 - 7824
(2014/06/23)
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- Transition-metal-free and chemoselective NaOtBu-O 2-mediated oxidative cleavage reactions of vic-1,2-diols to carboxylic acids and mechanistic insight into the reaction pathways
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A method for efficient oxidative cleavage of vic-1,2-diols using a NaO tBu-O2 system resulted in the formation of carboxylic acids in high yields. The present protocol is an eco-friendly alternative to a conventional transition-metal-based method. This new strategy allows large-scale production with nonchromatographic purification while also suppressing competitive reaction pathway such as benzilic acid rearrangement.
- Kim, Sun Min,Kim, Dong Wan,Yang, Jung Woon
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supporting information
p. 2876 - 2879
(2014/06/23)
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- Reactivity of an iron-oxygen oxidant generated upon oxidative decarboxylation of biomimetic iron(II) α-hydroxy acid complexes
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Three biomimetic iron(II) α-hydroxy acid complexes, [(Tp Ph2)FeII(mandelate)(H2O)] (1), [(Tp Ph2)FeII(benzilate)] (2), and [(TpPh2)Fe II(HMP)] (3), together with two iron(II) α-methoxy acid complexes, [(TpPh2)FeII(MPA)] (4) and [(Tp Ph2)FeII(MMP)] (5) (where HMP = 2-hydroxy-2- methylpropanoate, MPA = 2-methoxy-2-phenylacetate, and MMP = 2-methoxy-2-methylpropanoate), of a facial tridentate ligand TpPh2 [where TpPh2 = hydrotris(3,5-diphenylpyrazole-1-yl)borate] were isolated and characterized to study the mechanism of dioxygen activation at the iron(II) centers. Single-crystal X-ray structural analyses of 1, 2, and 5 were performed to assess the binding mode of an α-hydroxy/methoxy acid anion to the iron(II) center. While the iron(II) α-methoxy acid complexes are unreactive toward dioxygen, the iron(II) α-hydroxy acid complexes undergo oxidative decarboxylation, implying the importance of the hydroxyl group in the activation of dioxygen. In the reaction with dioxygen, the iron(II) α-hydroxy acid complexes form iron(III) phenolate complexes of a modified ligand (TpPh2*), where the ortho position of one of the phenyl rings of TpPh2 gets hydroxylated. The iron(II) mandelate complex (1), upon decarboxylation of mandelate, affords a mixture of benzaldehyde (67%), benzoic acid (20%), and benzyl alcohol (10%). On the other hand, complexes 2 and 3 react with dioxygen to form benzophenone and acetone, respectively. The intramolecular ligand hydroxylation gets inhibited in the presence of external intercepting agents. Reactions of 1 and 2 with dioxygen in the presence of an excess amount of alkenes result in the formation of the corresponding cis-diols in good yield. The incorporation of both oxygen atoms of dioxygen into the diol products is confirmed by 18O-labeling studies. On the basis of reactivity and mechanistic studies, the generation of a nucleophilic iron-oxygen intermediate upon decarboxylation of the coordinated α-hydroxy acids is proposed as the active oxidant. The novel iron-oxygen intermediate oxidizes various substrates like sulfide, fluorene, toluene, ethylbenzene, and benzaldehyde. The oxidant oxidizes benzaldehyde to benzoic acid and also participates in the Cannizzaro reaction.
- Paria, Sayantan,Chatterjee, Sayanti,Paine, Tapan Kanti
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supporting information
p. 2810 - 2821
(2014/04/03)
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- Stepwise oxygenations of toluene and 4-nitrotoluene by a fungal peroxygenase
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Fungal peroxygenases have recently been shown to catalyze remarkable oxidation reactions. The present study addresses the mechanism of benzylic oxygenations catalyzed by the extracellular peroxygenase of the agaric basidiomycete Agrocybe aegerita. The peroxygenase oxidized toluene and 4-nitrotoluene via the corresponding alcohols and aldehydes to give benzoic acids. The reactions proceeded stepwise with total conversions of 93% for toluene and 12% for 4-nitrotoluene. Using H218O2 as the co-substrate, we show here that H2O2 is the source of the oxygen introduced at each reaction step. A. aegerita peroxygenase resembles cytochromes P450 and heme chloroperoxidase in catalyzing benzylic hydroxylations.
- Kinne, Matthias,Zeisig, Christian,Ullrich, Rene,Kayser, Gernot,Hammel, Kenneth E.,Hofrichter, Martin
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- Enantiopure chiral (2,4,6-triisopropylbenzoyl)oxy-[D1] methyllithium: Configurational stability, reactions, and mechanistic studies
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The configurational stability of enantiopure chiral (2,4,6- triisopropylbenzoyl)oxy-[D1]methyllithium generated by a tin-lithium exchange was tested on the macroscopic time scale, employing trapping experiments with benzaldehyde. It was found t
- Kapeller, Dagmar C.,Hammerschmidt, Friedrich
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supporting information; experimental part
p. 2380 - 2388
(2009/08/08)
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- Chemoenzymatic synthesis of ring18O-labeled sialic acid
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Methyl 4,6-O-benzylidene-α-D-glucopyranoside was converted into methyl 2-azido-2-deoxy-4,6-O-benzylidene-α-D-altropyranoside via a synthetic route that incorporated two inversions of configuration. Activation of the C-3 hydroxyl group as a triflate ester
- Indurugalla, Deepani,Bennet, Andrew J.
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experimental part
p. 1005 - 1009
(2009/02/08)
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- Partial oxygen migration in the photochemical wolff rearrangement - α-Oxocarben-Oxiren-isomerization or intermolecular mechanism?
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Crossover experiments between isotopomeric species of 2-diazo-1-oxo-1-phenylethane (18O, 13C, D) establish beyond doubt that the oxygen migration accompanying the photochemical Wolff rearrangement is not the result of intermolecular
- Haiss, Peter,Zeller, Klaus-Peter
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p. 595 - 605
(2007/10/03)
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- Loss of isotope labeling in the conversion of [18O2]benzoic acid into [18O]benzoyl chloride with oxalyl chloride
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Tell me where the 18O atoms are, where are they to be found? This question was raised when a large amount of the 18O labeling was lost in the course of the conversion of [18O2]benzoic acid into [18O]b
- Haiss, Peter,Zeller, Klaus-Peter
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p. 303 - 305
(2007/10/03)
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- Stereodefined synthesis of O3′-labeled uracil nucleosides. 3′-[17O]-2′-azido-2′-deoxyuridine 5′-diphosphate as a probe for the mechanism of inactivation of ribonucleotide reductases
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Thermolysis of a 2′-[16O]-O-benzoyl-[17O]-5′-O-(tert- butyldimethylsilyl)-O2,3′-cyclouridine derivative gave the more stable 3′-[17O]-O-benzoyl-[16O]-5′-O-(tert- butyldimethylsilyl)-O2,2′-cyclouridine isomer, which was converted into 3′-[17O]-2′-azido-2′-deoxyuridine by deprotection and nucleophilic ring opening at C2′ with lithium azide. The 5′-diphosphate was prepared by nucleophilic displacement of the 5′-O-tosyl group with tris(tetrabutylammonium) hydrogen pyrophosphate. Model reactions gave 16O and 18O isotopomers, and base-promoted hydrolysis of an O2,2′-cyclonucleoside gave stereodefined access to 3′-[18O]-1-(β-D-arabinofuranosyl)uracil. Inactivation of ribonucleoside diphosphate reductase with 2′-azido-2′-deoxynucleotides results in appearance of EPR signals for a nitrogen-centered radical derived from azide, and 3′-[17O]-2′-azido-2′-deoxyuridine 5′-diphosphate provides an isotopomer to perturb EPR spectra in a predictable manner.
- Wnuk, Stanislaw F.,Chowdhury, Saiful M.,Garcia Jr., Pedro I.,Robins, Morris J.
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p. 1816 - 1819
(2007/10/03)
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- Hydrolysis of phosphotriesters: Determination of transition states in parallel reactions by heavy-atom isotope effects
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The remote label method was used to measure primary and secondary 18O isotope effects in the alkaline hydrolysis of O,O-diethylphosphorylcholine iodide (DEPC) and the primary 18O effect in the alkaline hydrolysis of O,O-diethyl-m-nitrobenzyl phosphate (DEmNBP). Both the leaving group of interest (choline or m-nitrobenzyl alcohol) and ethanol can be ejected during hydrolysis due to the similarity of their pK values. The heavy-atom isotope effects were measured by isotope ratio mass spectrometry. Parallel reaction and incomplete labeling corrections were made for both systems. DEPC has a primary 18O isotope effect of 1.041 ± 0.003 and a secondary 18O isotope effect of 1.033 ± 0.002. The primary 18O isotope effect for DEmNBP was 1.052 ± 0.003. These large effects suggest a highly associative transition state in which the nucleophile approaches very close to the phosphorus atom to eject the leaving group. The large values are also indicative of a large compression, or general movement, on the reaction coordinate.
- Anderson,Shim,Raushel,Cleland
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p. 9246 - 9253
(2007/10/03)
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- Mechanism of the Replacement of Phenolic Hydroxyl by Carbonyl on Lead Tetraacetate Treatment of o-Hydroxyaryl Ketone Acylhydrazones
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A mechanistic study has been carried out on the reaction of acylhydrazones of o-hydroxyaryl ketones 6 with lead tetraacetate, which gives 1,2-diacylbenzenes 7 by a novel overall replacement of phenolic hydroxyl with an acyl group.Cross-over experiments de
- Katritzky, Alan R.,Harris, Philip A.,Kotali, Antigoni
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p. 5049 - 5051
(2007/10/02)
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- Reactive Iron Porphyrin Derivatives Related to the Catalytic Cycles of Cytochrome P-450 and Peroxidase. Studies of the Mechanism of Oxygen Activation
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The mechanism of oxidation of tetramesityliron(III) porphyrins IIITMP(X)> with peroxyacids has been examined.The reaction of FeIIITMP(Cl) (1) with peroxyacids in methylene chloride at -46 deg C afforded the corresponding oxoiron(IV) porphyrin cation radical IVTMP.+(O)> (3).The kinetics of this process were complicated by an induction period that depended on the acidity of the peroxyacid used.By contrast, similar oxidations of FeIIITMP(OH) gave evidence for rapid ligand metathesis to afford an acylperoxoiron(III) complex FeIIITMP(OOC(O)Ar) (2).The decomposition of 2 to form 3 was found to be first order in 2 and catalyzed by acid.Electron-withdrawing substituents on the aryl portion of the peroxyacid facilitated this reaction (ρ = +0.5).The temperature dependence between -32 and -48 deg C indicated Ea = 4 +/- 0.4 kcal/mol, ΔH* = 3.6 +/- 0.4 kcal/mol, and ΔS* > -25 eu.The oxidation of 1-(m-chlorobenzoate) in toluene with peroxyacids afforded an iron(III) porphyrin N-oxide (5).The reaction required 2 equiv of peroxyacid and afforded 1 mol of a diacylperoxide.The presence of acid discouraged the formation of 5.Substituent effects in the peroxyacid were the opposite for the formation of 5 (ρ = -0.4) than the formation of 3.The results indicated that there are competing homolytic and heterolytic O-O bond cleavage reactions for 2 mediated by iron(III).
- Groves, John T.,Watanabe, Yoshihito
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p. 8443 - 8452
(2007/10/02)
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