bluuebunny/crossref_metadata_2025 huggingface dataset:
An intelligent tutor for teaching software design patterns
Authors: Berdun Luis , Amandi Analia , Campo Marcelo
Published: October 2011

How to teach students to design in the classroom? When is experience crucial to do design? In particular, how to teach design patterns to students who are beginning to know the importance of a good design? Experience is essential to understand and apply patterns in an effective way. Generally, novice users are not good at working in real experiences while they are good at learning new techniques and methods for designing. In this work, we show the results of teaching patterns using an artificial intelligent assistant that helps novice developers during the design process. Our assistant is an interface agent that observes novice users working, and when it detects that a design pattern can be applied, it makes a suggestion justifying its opinion. Thus, students understand when and where a pattern could be applied.© 2011 Wiley Periodicals, Inc. Comput Appl Eng Educ 22:583–592, 2014; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.20582
Characterization of Optimal Aptamer‐Microarray Binding Chemistry and Spacer Design
Authors: Zhu G. , Lübbecke M. , Walter J.‐G. , Stahl F. , Scheper T.
Published: November 2011

Compared to conventional protein microarrays, the aptamer microarray is a relatively new and competitive method for analytical applications. The three‐dimensional folded aptamers show excellent binding specificity and affinity, and thus, can be used as an alternative to antibodies. Immobilization and binding effects of aptamers under different combinations of surfaces and spacers for aptamer‐microarray applications are investigated. In addition, the effects of spacers integrated at the terminal position of aptamers on made in‐house and commercially available microarray supports are explored.
Alkaline Hydrolysis of an Aromatic Ester: Kinetic Studies Using Thermal Power Profiles
Authors: Pečar D. , Goršek A.
Published: November 2011

The reaction kinetics of ethyl benzoate saponification with sodium hydroxide in a heterogeneous reaction medium was investigated. The rate of reaction in a heterogeneous liquid‐liquid system incorporates a chemical kinetics term as well as the mass transfer between both phases. The reaction was carried out in a reaction calorimeter and the overall reaction rate was determined from the obtained thermal profiles. The mass transfer parameters were calculated numerically, taking into account those reaction rate constants determined in our previous study, where the above‐mentioned reaction was conducted in a homogeneous reaction medium. The dependence of the mass transfer parameters and reaction rates on different heterogeneity stages and temperatures is described.
Hydrothermal Carbonization – 1. Influence of Lignin in Lignocelluloses
Authors: Dinjus E. , Kruse A. , Tröger N.
Published: November 2011

Hydrothermal carbonization is an attractive process for converting biomass with high water content into different products. The requirements on the products, which may be soil improvement or substitution of lignite or carbon black, are opposed to biomass as a feedstock that has a very complex and variable composition. The goal of this work was to study the influence of an ingredient, here lignin, on carbonization, with the focus being not only on the composition but also on the structure of the product formed.
Organometallic Complexes in Supported Ionic‐Liquid Phase (SILP) Catalysts: A PHIP NMR Spectroscopy Study
Authors: Gong Qingxia , Klankermayer Jürgen , Blümich Bernhard
Published: November 2011

para‐Hydrogen induced polarization (PHIP) NMR spectroscopy emerges as an efficient and robust method for on‐line monitoring of gas‐phase hydrogenation reactions. Here we report detailed investigations of supported ionic liquid phase (SILP) catalysts in a continuous gas‐phase hydrogenation of propene with PHIP NMR spectroscopy. A relocation of the rhodium complex in the thin layer of ionic liquid in the SILP catalyst at the initial stage of the propene hydrogenation is demonstrated. PHIP NMR spectroscopy can provide profound insight into the evolution of SILP catalysts during hydrogenation reactions.
Spectroscopic, Morphological, and Mechanistic Investigation of the Solvent‐Promoted Aggregation of Porphyrins Modified in meso‐Positions by Glucosylated Steroids
Authors: Zelenka Karel , Trnka Tomáš , Tišlerová Iva , Monti Donato , Cinti Stefano , Naitana Mario Luigi , Schiaffino Luca , Venanzi Mariano , Laguzzi Giuseppe , Luvidi Loredana , Mancini Giovanna , Nováková Zdena , Šimák Ondřej , Wimmer Zdeněk , Drašar Pavel
Published: November 2011

Solvent‐driven aggregation of a series of porphyrin derivatives was studied by UV/Vis and circular dichroism spectroscopy. The porphyrins are characterised by the presence in the meso positions of steroidal moieties further conjugated with glucosyl groups. The presence of these groups makes the investigated macrocycles amphiphilic and soluble in aqueous solvent, namely, dimethyl acetamide/water. Aggregation of the macrocycles is triggered by a change in bulk solvent composition leading to formation of large architectures that express supramolecular chirality, steered by the presence of the stereogenic centres on the periphery of the macrocycles. The aggregation behaviour and chiroptical features of the aggregates are strongly dependent on the number of moieties decorating the periphery of the porphyrin framework. In particular, experimental evidence indicates that the structure of the steroid linker dictates the overall chirality of the supramolecular architectures. Moreover, the porphyrin concentration strongly affects the aggregation mechanism and the CD intensities of the spectra. Notably, AFM investigations reveal strong differences in aggregate morphology that are dependent on the nature of the appended functional groups, and closely in line with the changes in aggregation mechanism. The suprastructures formed at lower concentration show a network of long fibrous structures spanning over tens of micrometres, whereas the aggregates formed at higher concentration have smaller rod‐shaped structures that can be recognised as the result of coalescence of smaller globular structures. The fully steroid substituted derivative forms globular structures over the whole concentration range explored. Finally, a rationale for the aggregation phenomena was given by semiempirical calculations at the PM6 level.
Mechanistic Origin of Ligand‐Controlled Regioselectivity in Pd‐Catalyzed CH Activation/Arylation of Thiophenes
Authors: Tang Shi‐Ya , Guo Qing‐Xiang , Fu Yao
Published: November 2011

The use of ligands to control regioselectivity in transition‐metal‐catalyzed CH activation/functionalization is a highly desirable but challenging task. Recently, Itami et al. reported an important finding relating to Pd‐catalyzed ligand‐controlled α/β‐selective CH arylation of thiophenes. Specifically, the use of the 2,2′‐bipyridyl ligand resulted in α‐arylation, whereas the use of the bulky fluorinated phosphine ligand P[OCH(CF3)2]3 resulted in β‐arylation. Understanding of this surprising ligand‐controlled α/β‐selectivity could provide important insights into the development of more efficient catalyst systems for selective CH arylation, and so we carried out a detailed computational study on the problem with use of density functional theory methods. Three mechanistic possibilities—SEAr and migration, metalation/deprotonation, and Heck‐type arylation mechanisms—were examined. The results showed that the SEAr and migration mechanism might not be plausible, because the key Wheland intermediates could not be obtained. On the other hand, our study indicated that the metalation/deprotonation and Heck‐type arylation mechanisms were both involved in Itami’s reactions. In the metalation/deprotonation pathway the α‐selective product (C5‐product) was preferred, whereas in the Heck‐type arylation mechanism the β‐selective product (C4‐product) was favored. The ligands played crucial roles in tuning the relative barriers of the two different pathways. In the 2,2′‐bipyridyl‐assisted system, the metalation/deprotonation pathway was energetically advantageous, leading to α‐selectivity. In the P[OCH(CF3)2]3‐assisted system, on the other hand, the Heck‐type arylation mechanism was kinetically favored, leading to β‐selectivity. An interesting finding was that P[OCH(CF3)2]3 could produce a CH⋅⋅⋅O hydrogen bond in the catalyst system, which was crucial for stabilization of the Heck‐type transition state. In comparison, this CH⋅⋅⋅O hydrogen bond was absent with the other phosphine ligands [i.e., P(OMe)3, PPh3, PCy3] and these phosphine ligands therefore favored the metalation/deprotonation pathway leading to α‐selectivity. Furthermore, in this study we have provided theoretical evidence showing that the Heck‐type arylation reaction could proceed through an anti‐β‐hydride elimination process.
Assembling Phthalocyanine Dimers through a Platinum(II) Acetylide Linker
Authors: Jiménez Angel J. , Marcos M. Luisa , Hausmann Anita , Rodríguez‐Morgade M. Salomé , Guldi Dirk M. , Torres Tomás
Published: November 2011

Phthalocyanine (Pc) dimers connected through trans‐platinum(II) diacetylide linkers have been prepared by reaction of the corresponding ethynylphthalocyanines with trans‐bis(triethylphosphine)platinum(II) chloride. Special emphasis was placed on the analysis of the ground‐ and excited‐state features of these compounds in relation to butadiyne‐bridged Pc dimers and the corresponding monomers. Both ZnII‐containing Pc dimers exhibit long‐lived triplet excited states. The insertion of σ‐bonded trans‐platinum(II) diacetylide spacers decoupled the two Pc groups and led to an appreciable acceleration (by a factor of up to 10) of the radiative and nonradiative decay rate of the singlet and triplet excited states.
Multifunctional and Reactive Enantiopure Organometallic Helicenes: Tuning Chiroptical Properties by Structural Variations of Mono‐ and Bis(platinahelicene)s
Authors: Anger Emmanuel , Rudolph Mark , Norel Lucie , Zrig Samia , Shen Chengshuo , Vanthuyne Nicolas , Toupet Loïc , Williams J. A. Gareth , Roussel Christian , Autschbach Jochen , Crassous Jeanne , Réau Régis
Published: November 2011

Acetylacetonato‐platina[6]‐ and ‐platina[7]helicenes have been prepared from 2‐pyridyl‐substituted benzophenanthrene ligands by following a two‐step cycloplatination reaction. The photophysical properties (UV‐visible absorption and emission behavior) and chiroptical properties (circular dichroism and molar rotation) of the resolved enantiomers have been measured. These metallahelicenes constitute a novel family of easily accessible helicene derivatives that exhibit large and tuneable chiroptical properties that can be rationalized theoretically and compared to the parent [6]‐ and [7]carbohelicenes. Furthermore, they are red phosphors at room temperature and their large chiroptical properties can be modulated by oxidation of the metal center to PtIV. Hetero‐ and homochiral diastereomeric bis(metallahelicene)s that possess a rare PtIIIPtIII scaffold bridged by benzoato ligands have also been prepared. It is shown that the heterochiral (P,M)‐bis(PtIII–[6]helicene) 9 a1 can isomerize into the homochiral (P,P)‐ and (M,M)‐bis(PtIII–[6]helicene) 9 a2. Spectral assignments and an analysis of the optical rotation of these systems were made with the help of time‐dependent density functional theory. The calculations highlight the contributions of the metal centers to the chiroptical properties. For 9 a1 and 9 a2, σ–π conjugation between the helicenes and the PtPt moiety may contribute strongly to the optical rotation and electronic circular dichroism.
Synthesis, Crystal and Electronic Structures, and Magnetic Properties of LiLn9Mo16O35 (Ln=La, Ce, Pr, and Nd) Compounds Containing the Original Cluster Mo16O36
Authors: Gougeon Patrick , Gall Philippe , Cuny Jérôme , Gautier Régis , Le Pollès Laurent , Delevoye Laurent , Trébosc Julien
Published: November 2011

The new compounds LiLn9Mo16O35 (Ln=La, Ce, Pr, and Nd) were synthesized from stoichiometric mixtures of Li2MoO4, Ln2O3, Pr6O11 or CeO2, MoO3, and Mo heated at 1600 °C for 48 h in a molybdenum crucible sealed under a low argon pressure. The crystal structure, determined from a single crystal of the Nd member, showed that the main building block is the Mo16O36 unit, the Mo16 core of which is totally new and results from the fusion of two bioctahedral Mo10 clusters. It can also be viewed as a fragment of an infinite twin chain of edge‐sharing Mo6 octahedra. The Mo16O36 cluster units share some oxygen atoms to form infinite chains running parallel to the b axis, which are separated by the rare‐earth and lithium cations. 7Li‐NMR experiments, carried out at high field on the nonmagnetic LiLa9Mo16O35, provided insights into the local environment of the lithium ions. Magnetic susceptibility measurements confirmed the trivalent oxidation state of the magnetic rare‐earth cations and indicated the absence of localized moments on the Mo16 clusters. The electronic structure of the LiLn9Mo16O35 compounds was analyzed using molecular and periodic quantum calculations. The study of the molecular orbital diagrams of isolated Mo16O36 models allowed the understanding of this unique metallic architecture. Periodic density functional theory calculations demonstrated that few interactions occur between the Mo16 clusters, and predicted semiconducting properties for LiLn9Mo16O35 as a band gap of 0.57 eV was computed for the lanthanum phase.
ChemInform Abstract: Crystal Structure, Charge Transport, and Magnetic Properties of MnSb2Se4.
Authors: Djieutedjeu Honore , Makongo Julien P. A. , Rotaru Aurelian , Palasyuk Andriy , Takas Nathan J. , Zhou Xiaoyuan , Ranmohotti Kulugammana G. S. , Spinu Leonard , Uher Citrad , Poudeu Pierre F. P.
Published: November 2011

The title compound is synthesized by solid state reaction of a stoichiometric mixture of the elements (573 K for 48 h and 773 K for 72 h).
ChemInform Abstract: Crystal Water Molecules as Magnetic Tuners in Molecular Metamagnets Exhibiting Antiferro—Ferro—Paramagnetic Transitions.
Authors: Herchel Radovan , Tucek Jiri , Travnicek Zdenek , Petridis Dimitris , Zboril Radek
Published: November 2011

Compounds (III)—(V) are characterized by 57Fe Moessbauer spectroscopy, single crystal XRD for (III) and (V), and magnetization measurements to study the effects of the number of crystal water molecules on the magnetic behavior.
ChemInform Abstract: Aluminum Germanides of the Divalent Lanthanoides Eu and Yb: Synthesis, Structural Chemistry and Chemical Bonding.
Authors: Bauer Britta , Roehr Caroline
Published: November 2011

The new compounds Eu3Al2Ge4 (I), Eu3Al1.8Ge2.2 (II), Yb2AlGe3 (III), and Yb17Al8Ge19 (IV) are synthesized by melting mixtures of the elements and their structures are determined by single crystal XRD.
ChemInform Abstract: mer‐Triammine Trifluorido Iron(III), mer‐[FeF3(NH3)3].
Authors: Kraus Florian , Baer Sebastian A.
Published: November 2011

The title compound is synthesized in quantitative yield by reaction of FeF3 with liquid NH3 at ‐40 °C.
ChemInform Abstract: Ternary Antimonides Ln2Ir3Sb4 (Ln: La, Ce, Pr, Nd).
Authors: Schaefer Konrad , Hermes Wilfried , Rodewald Ute Ch. , Hoffmann Rolf‐Dieter , Poettgen Rainer
Published: November 2011

The title compounds are obtained from stoichiometric melts of the elements and their structure is determined by single crystal XRD.
ChemInform Abstract: Diastereoselective Preparation of (S)‐(1,4,4‐Trimethylpyrrolidin‐3‐yl)amine, a New Chiral 1,2‐Diamine for Thiourea‐Type Organocatalysts.
Authors: Camps Pelayo , Galdeano Carles , Munoz‐Torrero Diego , Rull Jordi , Calvet Teresa , Font‐Bardia Merce
Published: November 2011

PTU is used in several enantioselective Michael reactions of trans‐β‐nitrostyrene (I) with 1,3‐dicarbonyl compounds.
ChemInform Abstract: Rhodium(I)‐Catalyzed Ene—Allene—Allene [2 + 2 + 2] Cycloadditions: Stereoselective Synthesis of Complex trans‐Fused Carbocycles.
Authors: Brusoe Andrew T. , Alexanian Erik J.
Published: November 2011

A variety of trans‐fused hydrindans and decalins is synthesized with complete stereochemistry, except for the (Z)‐isomer (IV).
ChemInform Abstract: The Intramolecular Asymmetric Allylation of Aldehydes via Organo‐SOMO Catalysis: A Novel Approach to Ring Construction.
Authors: Pham Phong V. , Ashton Kate , MacMillan David W. C.
Published: November 2011

Selective oxidation of chiral enamines generated in situ by condensation of an aldehyde and a secondary amine catalyst, and subsequent cyclization provide a new approach to five‐, six‐ and seven‐membered carbocycles.
ChemInform Abstract: Anhydrous FePO4 as a Cost‐Effective and Recyclable Catalyst for Tetrahydropyranylation and Tetrahydrofuranylation of Alcohols and Phenols
Authors: Behbahani Farahnaz K. , Farahani Mona
Published: November 2011

as well as their deprotection
ChemInform Abstract: Unexpected Formation of (E)‐4‐Alkene 1,3‐Diketones from the Three‐Component Reaction of Lithium Selenolates with 1‐(1‐Alkynyl)cyclopropyl Ketones and Aldehydes.
Authors: Xu Jianfeng , Wu Luling , Huang Xian
Published: November 2011

The diketones can smoothly be converted into isoxazoles, pyrazoles, and other derivatives like (VII).
ChemInform Abstract: Stereospecific Synthesis of syn‐α‐Oximinoamides by a Three‐Component Reaction of Isocyanides, syn‐Chlorooximes, and Carboxylic Acids.
Authors: Pirali Tracey , Mossetti Riccardo , Galli Simona , Tron Gian Cesare
Published: November 2011

A small library of biologically relevant title compounds is prepared.
ChemInform Abstract: Homologous Mukaiyama Reactions via Trapping of the Nazarov Intermediate with Silyloxyalkenes.
Authors: Wu Yen‐Ku , McDonald Robert , West F. G.
Published: November 2011

The domino reaction of various 1,4‐pentadien‐3‐ones and silyloxyalkenes results in formation of 1,4‐dicarbonyl products bearing highly substituted cyclopentanones with up to five new stereocenters.
ChemInform Abstract: One‐Pot Synthesis of (E)‐Styryl Ketones from Styrenes.
Authors: Pawluc Piotr , Szudkowska Justyna , Hreczycho Grzegorz , Marciniec Bogdan
Published: November 2011

A new, efficient, and selective method is reported.
ChemInform Abstract: Cu‐Mediated Chemoselective Trifluoromethylation of Benzyl Bromides Using Shelf‐Stable Electrophilic Trifluoromethylating Reagents.
Authors: Kawai Hiroyuki , Furukawa Tasuya , Nomura Yoshinori , Tokunaga Etsuko , Shibata Norio
Published: November 2011

The reaction is general and tolerates various functional groups.
ChemInform Abstract: Reduction of Hydrazines to Amines with Aqueous Solution of Titanium(III) Trichloride.
Authors: Zhang Yan , Tang Qiang , Luo Meiming
Published: November 2011

The new method is compatible with C=C, Bn—N, Cbz—N‐ and Ac—N bonds and proceeds under a broad pH range from acidic to neutral and basic conditions to afford the corresponding primary and secondary amines.
ChemInform Abstract: A Novel Method for Tosyloxylation of Anilides Using Phenyliodine Bistrifluoroacetate (PIFA).
Authors: Liu Huan , Xie Yuanzhen , Gu Yonghong
Published: November 2011

In all cases p‐substituted anilines are obtained with high regioselectivity.
ChemInform Abstract: Ligand‐Free Highly Effective Iron/Copper Cocatalyzed Formation of Dimeric Aryl Ethers or Sulfides.
Authors: Qu Xiaoming , Li Tingyi , Zhu Yan , Sun Peng , Yang Hailong , Mao Jincheng
Published: November 2011

The Fe/Cu cocatalyzed coupling of diiodoarenes (I) with phenols (IV) or benzenethiol (II) provides an efficient access towards dimeric arylethers (V) or thioethers (III).
ChemInform Abstract: Copper‐Catalyzed Rearrangement of Oximes into Primary Amides.
Authors: Sharma Sumeet K. , Bishopp Simon D. , Allen C. Liana , Lawrence Ruth , Bamford Mark J. , Lapkin Alexei A. , Plucinski Pawel , Watson Robert J. , Williams Jonathan M. J.
Published: November 2011

The process is efficient under thermal and microwave conditions in the presence of Cu(O‐Ac)2.
ChemInform Abstract: Regioselective Cobalt‐Catalyzed Addition of Sulfides to Unactivated Alkenes.
Authors: Girijavallabhan Vinay , Alvarez Carmen , Njoroge F. George
Published: November 2011

It provides a new and mild method to prepare secondary and tertiary alkyl and aryl sulfides.
ChemInform Abstract: Vanadium‐Catalyzed Enantioselective Oxidation of Allyl Sulfides.
Authors: Zeng Qingle , Gao Yuxing , Dong Junyu , Weng Wen , Zhao Yufen
Published: November 2011

Allyl and cinnamyl sulfides (I) are efficiently converted into chiral allyl sulfoxides using a new vanadyl complex of 3,5‐diiodosalicylidene tert‐leucinol.
ChemInform Abstract: New Ligands that Promote Cross‐Coupling Reactions Between Aryl Halides and Unactivated Arenes.
Authors: Qiu Yatao , Liu Yanghan , Yang Kai , Hong Wenkun , Li Zheng , Wang Zhaoyang , Yao Zhiyi , Jiang Sheng
Published: November 2011

A wide range of aromatic and heteroaromatic aryl iodides and bromides react with arenes using quinoline‐1‐amino‐2‐carboxylic acid as a catalyst to afford the corresponding cross‐coupling products.
ChemInform Abstract: Highly Efficient Synthesis of β‐Amino Ketones via Direct Mannich‐Type Reaction Catalyzed by Acidic Ionic Liquid.
Authors: Zhang Dong‐Nuan , Li Ji‐Tai , Song Ya‐Li , Chen Guo‐Feng
Published: November 2011

An ionic liquid‐catalyzed one‐pot three‐component Mannich‐type reaction of aromatic aldehydes, aromatic amines and cyclohexanone is presented.
ChemInform Abstract: Palladium‐Catalyzed Oxidative Rearrangement of Diaryl Alkenyl Carbinols to β,β‐Diaryl α,β‐Unsaturated Ketones.
Authors: Rosa David , Orellana Arturo
Published: November 2011

The reaction proceeds with complete stereoselectivity when a substrate bears one ortho‐substituted aromatic ring but is not sensitive to electronic effects.
ChemInform Abstract: 3‐(Hetero)aryl‐4‐indolylamino‐α‐tetralones by Diastereoselective Internal Redox Cyclization: An “Azaenamine” Conjugate Addition.
Authors: Ghavtadze Nugzar , Narayan Rishikesh , Wibbeling Birgit , Wuerthwein Ernst‐Ulrich
Published: November 2011

Treatment of hydrazones of type (I) with BF3·SMe2 is found to allow new and diastereoselective access to biologically important trans‐substituted tetralones like (II).
ChemInform Abstract: Intramolecular Friedel—Crafts Alkylation of Chalcone Epoxides Using Indium(III) Chloride as an Efficient Catalyst.
Authors: Ahmed Naseem , Babu V. Venkata , Kumar Harendra
Published: November 2011

InCl3 is explored as the most efficient catalyst for the preparation of highly functionalized cis‐2‐hydroxyindanones.
ChemInform Abstract: Alkali Metal Mediated Zincation of N‐Heterocyclic Substrates Using the Lithium Zincate Complex, (THF)Li(TMP)Zn(tBu)2 and Applications in in situ Cross‐Coupling Reactions.
Authors: Blair Victoria L. , Blakemore David C. , Hay Duncan , Hevia Eva , Pryde David C.
Published: November 2011

The direct regioselective zincation is studied and the resulting zinc organics are quenched with iodine or employed in Pd‐catalyzed Negishi cross‐coupling reactions.
ChemInform Abstract: A Simple, Iron‐Catalyzed, Pyridine‐Assisted Hydrogen Peroxide Epoxidation System.
Authors: Jiao Mingyu , Matsunaga Hirofumi , Ishizuka Tadao
Published: November 2011

A simple and inexpensive catalytic system for the olefin epoxidation is presented.
ChemInform Abstract: Regioselective Transformation of O‐Propargylic Arylaldoximines to Four‐Membered Cyclic Nitrones by Copper‐Catalyzed Skeletal Rearrangement.
Authors: Nakamura Itaru , Araki Toshiharu , Zhang Dong , Kudo Yu , Kwon Eunsang , Terada Masahiro
Published: November 2011

The reaction proceeds via tandem [2,3]‐rearrangement of the O‐propargylic arylaldoximes and 4π‐electrocyclization of the intermediate N‐allenylnitrones.
ChemInform Abstract: Alternative Pathways for Heck Intermediates: Palladium‐Catalyzed Oxyarylation of Homoallylic Alcohols.
Authors: Zhu Chen , Falck John R.
Published: November 2011

Oxidative Heck arylation of homoallylic alcohols occurs in the presence of TFA affording α‐aryltetrahydrofurans in good yields and regioselectivities.
ChemInform Abstract: Rh‐Catalyzed Transannulation of N‐Tosyl‐1,2,3‐triazoles with Terminal Alkynes.
Authors: Chattopadhyay Buddhadeb , Gevorgyan Vladimir
Published: November 2011

The reaction is applied to electron‐rich terminal aryl alkynes including sterically congested ones and to triazoles with aromatic substituents, ester or alkyl groups to produce substituted N‐Tos‐pyrrole derivatives.
ChemInform Abstract: Microwave‐Assisted Synthesis of Indole‐Annulated Dihydropyrano[3,4‐c]chromene Derivatives via Hetero‐Diels—Alder Reaction.
Authors: Jha Mukund , Guy Stephanie , Chou Ting‐Yi
Published: November 2011

Knoevenagel condensation of salicylaldehyde derivatives with indolin‐3‐ones affords the precursors of type (III) with yields <85%.
ChemInform Abstract: Tetrasubstituted 2‐Imidazolones via Ag(I)‐Catalyzed Cycloisomerization of Propargylic Ureas.
Authors: Peshkov Vsevolod A. , Pereshivko Olga P. , Sharma Sweta , Meganathan Thirumal , Parmar Virinder S. , Ermolat'ev Denis S. , Van der Eycken Erik V.
Published: November 2011

A new and efficient one‐pot method to prepare tri‐ and tetrasubstituted 2‐imidazoles is reported.
ChemInform Abstract: Highly Enantioselective Catalytic Synthesis of Functionalized Chiral Diazoacetoacetates.
Authors: Xu Xinfang , Hu Wen‐Hao , Doyle Michael P.
Published: November 2011

A highly enantioselective Mukaiyama—Michael addition is presented to deliver the title compounds.
ChemInform Abstract: A Simple and Efficient Method for the Synthesis of Highly Substituted Imidazoles Using 3‐Aroylquinoxalin‐2(1H)‐ones.
Authors: Mamedov Vakhid A. , Zhukova Nataliya A. , Beschastnova Tat'yana N. , Gubaidullin Aidar T. , Rakov Dimitry V. , Rizvanov Il'dar Kh.
Published: November 2011

Benzoylquinoxalinone (I) is used as an hetero analogue of α‐diketones in the three‐component reaction.
ChemInform Abstract: A Multicomponent Coupling Reaction Induced by Insertion of Arynes into the C=O Bond of Formamide.
Authors: Yoshioka Eito , Kohtani Shigeru , Miyabe Hideto
Published: November 2011

Synthesis of various chromene and coumarin derivatives is achieved by three‐component coupling of aryne precursors, dimethylformamide and active methylenes under neutral conditions.
ChemInform Abstract: Synthesis of Some Fluorine‐Containing Pyridinealdoximes of Potential Use for the Treatment of Organophosphorus Nerve‐Agent Poisoning.
Authors: Timperley Christopher M. , Banks R. Eric , Young Ian M. , Haszeldine Robert N.
Published: November 2011

A series of fluorine‐containing pyridinealdoximes is synthesized and evaluated for their potential for treating nerve agents poisoning.
ChemInform Abstract: UV Promoted Phenanthridine Syntheses from Oxime Carbonate Derived Iminyl Radicals.
Authors: McBurney Roy T. , Slawin Alexandra M. Z. , Smart Laura A. , Yu Yanping , Walton John C.
Published: November 2011

Oxime carbonates (I), (III), (V) and (VII) are found to be excellent precursors for the generation of iminyl radicals under UV irradiation.
ChemInform Abstract: Copper‐Catalyzed Tandem Reaction of Isocyanides with N‐(2‐Haloaryl)propiolamides for the Synthesis of Pyrrolo[3,2‐c]quinolin‐4‐ones.
Authors: Zhou Fengtao , Liu Jianguang , Ding Ke , Liu Jinsong , Cai Qian
Published: November 2011

A new, simple, and efficient method is reported.
ChemInform Abstract: Synthesis and Evaluation of Highly Potent GABAA Receptor Antagonists Based on Gabazine (SR‐95531).
Authors: Iqbal Favaad , Ellwood Ryan , Mortensen Martin , Smart Trevor G. , Baker James R.
Published: November 2011

The compounds (VIa) and (VII) are highly potent GABAA receptor antagonists compared to the parent antagonist gabazine.
ChemInform Abstract: Synthesis and Substitution Reactions of 4(6)‐Chlorodihydropyrimidines.
Authors: Cho Hidetsura , Yasui Yoshizumi , Kobayashi Satoshi , Kwon Eunsang , Arisawa Mieko , Yamaguchi Masahiko
Published: November 2011

Cross‐coupling reactions at the 4‐position of dihydropyrimidine derivative (IV) are performed with organoboronic acids or triethylborane to afford dihydropyrimidines (VI), (IX), and (XI) having a variety of functional groups.
ChemInform Abstract: An Easy Entry into 2‐Halo‐3‐aryl‐4(3H)quinazoliniminium Halides from Heteroenyne‐Allenes.
Authors: Naganaboina Vijaya Kumar , Chandra Kusum Lata , Desper John , Rayat Sundeep
Published: November 2011

The method is general and is not sensitive to electronic effects of the substituents.
ChemInform Abstract: Annulation and Evaluation of Antibacterial Activity of the New Fused Tricyclic (5,5,6) Ring System of Pyrazolo[1,5‐c]‐1,2,4‐triazolo[4,3‐a]pyrimidines.
Authors: Atta Kamal F. M. , Marei Mohamed G. , Abd El‐Magiad Somia M. , El‐Nashar Faten H. A.
Published: November 2011

Reaction of pyrazolopyrimidines (I) with carbon disulfide (II) afford the new fused pyrazolotriazolopyrimidinethiones (III).
ChemInform Abstract: Regioselective Direct C—H Arylations of Protected Uracils. Synthesis of 5‐ and 6‐Aryluracil Bases.
Authors: Cernova Miroslava , Cerna Igor , Pohl Radek , Hocek Michal
Published: November 2011

New methods are reported.
ChemInform Abstract: Copper‐Catalyzed Aerobic Oxidative Intramolecular Alkene C—H Amination Leading to N‐Heterocycles.
Authors: Lu Juyou , Jin Yibao , Liu Hongxia , Jiang Yuyang , Fu Hua
Published: November 2011

The process affords the synthetically valuable N‐heterocycles as scaffolds of natural products with high yields.
ChemInform Abstract: Ion Pair Receptor Based on Anion—π Interaction.
Authors: Chen Yin , Wang De‐Xian , Huang Zhi‐Tang , Wang Mei‐Xiang
Published: November 2011

Novel azacrown (VI) is synthesized via a one‐pot reaction between triazine (I) and benzaldehyde (II), followed by condensation with diamine (IV) and reduction of the intermediate bisimine.
ChemInform Abstract: Sesquiterpenoids from the Formosan Soft Coral Lemnalia flava.
Authors: Su Jui‐Hsin , Lu Yi , Hung Wen‐Yu , Huang Chiung‐Yao , Chiang Michael Y. , Sung Ping‐Jyun , Kuo Yao‐Haur , Sheu Jyh‐Horng
Published: November 2011

Four new nardosinane‐type sesquiterpenoids, named flavalins E (I), F (II), G (III), and H (IV), and two new nornardosinane‐type norsesquiterpenoids, named flavalins I (V) and J (VI), are isolated along with five known compounds.
ChemInform Abstract: A New Polyoxygenated Triterpene and Two New Aeginetic Acid Quinovosides from the Roots of Rehmannia glutinosa.
Authors: Lee So Young , Kim Ju Sun , Choi Ran Joo , Kim Yeong Shik , Lee Je‐Hyun , Kang Sam Sik
Published: November 2011

The polyoxygenated triterpene, named glutinolic acid (I), and the two aeginetic acid quinovosides (II) are tested for their ability to inhibit NO production in LPS‐treated RAW 264.7 cells.
ChemInform Abstract: Composite Constituent: Lactucenyl Acetate, a Novel Migrated Lupane Triterpenoid from Lactuca indica Revision of Structure of Tarolupenyl Acetate.
Authors: Shinozaki Junichi , Nakane Takahisa , Onodera Naoe , Takano Akihito , Masuda Kazuo
Published: November 2011

The new lupan triterpenoid lactucenyl acetate (I) is isolated together with six known triterpenoids.
ChemInform Abstract: Eudistomidins H—K, New β‐Carboline Alkaloids from the Okinawan Marine Tunicate Eudistoma glaucus.
Authors: Suzuki Teppei , Kubota Takaaki , Kobayashi Jun'ichi
Published: November 2011

The four new β‐carboline alkaloids, eudistomidins H‐K (I)—(III), are isolated and their structures are elucidated based on spectroscopic data.
ChemInform Abstract: Chromanols from Sargassum siliquastrum and Their Antioxidant Activity in HT 1080 Cells.
Authors: Lee Jung Im , Seo Youngwan
Published: November 2011

The chromanols (I) and (II) are isolated together with the three known sargachromanols D, E, and K.
ChemInform Abstract: Ln2MO4 Cathode Materials for Solid Oxide Fuel Cells
Authors: Zhao Hui , Li Qiang , Sun Li Ping
Published: November 2011

Review: Ln: La, Pr, Nd, Sm; M: Ni, Cu, Fe, Co; 76 refs.
ChemInform Abstract: Recent Advances in the Coordination Chemistry of Nitrogen Monosulfide
Authors: Doessing Anders
Published: November 2011

Review: structure, reactivity, optical, photochemical, and magnetic properties of thioitrosyl complexes of transition metals; 75 refs.
ChemInform Abstract: Patterning of FePt for Magnetic Recording
Authors: Li G. J. , Leung C. W. , Lei Z. Q. , Lin K. W. , Lai P. T. , Pong Philip W. T.
Published: November 2011

Review: 50 refs.
ChemInform Abstract: Counterion Interaction and Association in Metal‐Oxide Cluster Macroanionic Solutions and the Consequent Self‐Assembly
Authors: Yin Panchao , Li Dong , Liu Tianbo
Published: November 2011

Review: 80 refs.
ChemInform Abstract: Can a Single Atom Serve as the Active Site in Some Heterogeneous Catalysts?
Authors: Thomas John Meurig , Saghi Zineb , Gai Pratibha L.
Published: November 2011

Review: 55 refs.
ChemInform Abstract: Chemistry of Polynuclear Transition‐Metal Complexes in Ionic Liquids
Authors: Ahmed Ejaz , Ruck Michael
Published: November 2011

Review: 122 refs.
ChemInform Abstract: Metal—Metal Multiple Bonds in Early/Late Heterobimetallic Complexes: Applications Toward Small Molecule Activation and Catalysis
Authors: Thomas ChristineM.
Published: November 2011

Review: 67 refs.
ChemInform Abstract: Some Chemical Transformations of Carbohydrates in Aqueous Medium
Authors: Queneau Yves , Pinel Catherine , Scherrmann Marie‐Christine
Published: November 2011

Review: 146 refs.
ChemInform Abstract: Molecular Selective Binding and Nano‐Fabrication of Cucurbituril/Cyclodextrin Pairs
Authors: Chen Yong , Zhang Ying‐Ming , Liu Yu
Published: November 2011

Review: 42 refs.
ChemInform Abstract: Enantioselective Hydrogen Bonding and Broensted Acid Mediated Organocatalysis
Authors: Lattanzi Alessandra
Published: November 2011

Review: 78 refs.
ChemInform Abstract: Cross‐Coupling Reactions of Organoboranes: An Easy Way to Construct C—C Bonds (Nobel Lecture)
Authors: Suzuki Akira
Published: November 2011

Review: 42 refs.
ChemInform Abstract: Magical Power of Transition Metals: Past, Present, and Future (Nobel Lecture)
Authors: Negishi Ei‐ichi
Published: November 2011

Review: 206 refs.
ChemInform Abstract: Huperzine A as Potential Treatment of Alzheimer′s Disease: An Assessment on Chemistry, Pharmacology, and Clinical Studies
Authors: Ha Giang T. , Wong Ryan K. , Zhang Yan
Published: November 2011

Review: 44 refs.
ChemInform Abstract: Synthesis and Reaction of Hypervalent λ3‐Iodane—Crown Ether Complexes
Authors: Miyamoto Kazunori
Published: November 2011

Review: 32 refs.
ChemInform Abstract: Recent Advances in [2 + 2 + 2] Cycloaddition Reactions
Authors: Dominguez Gema , Perez‐Castells Javier
Published: November 2011

Review: 53 refs.
ChemInform Abstract: Isolation, Chemical, and Biotransformation Routes of Labdane‐type Diterpenes
Authors: Frija Luis M. T. , Frade Raquel F. M. , Afonso Carlos A. M.
Published: November 2011

Review: 176 refs.
ChemInform Abstract: Formation of Ordered Nanoparticles Assemblies by Block Copolymer Lithography Methods
Authors: Terekhin V. V. , Dement'eva O. V. , Rudoy V. M.
Published: November 2011

Review: 234 refs.
ChemInform Abstract: Synthesis and Reactions of Pyrazolo[1,5‐a]pyridines and Related Heterocycles
Authors: Kendall Jackie D.
Published: November 2011

Review: 183 refs.
ChemInform Abstract: 1,2,4‐Triazine Chemistry. Part 1. Orientation of Cyclization Reactions of Functionalized 1,2,4‐Triazine Derivatives
Authors: Abdel‐Rahman Reda Mohammady , Makki Mohammed Saleh Tawfik , Ali Tarik El‐Sayed , Ibrahim Magdy Ahmed
Published: November 2011

Review: 58 refs.
ChemInform Abstract: Chemistry of Six‐Membered Cyclic Oxime Ethers: Application in the Synthesis of Bioactive Compounds
Authors: Sukhorukov Alexey Yu. , Ioffe Sema L.
Published: November 2011

Review: 225 refs.
ChemInform Abstract: Dehalogenative and Deprotonative Lithiation of Pyridines — A Second Wind for Trimethylsilylmethylithium (TmsCH2Li)
Authors: Gros Philippe C. , Fort Yves
Published: November 2011

Review: 62 refs.
ChemInform Abstract: Development of Transition Metal Catalyzed Cycloaddition Reactions Leading to Polycarbocyclic Systems
Authors: Gulias Moises , Lopez Fernando , Mascarenas Jose L.
Published: November 2011

Review: 40 refs.
ChemInform Abstract: Prolinethioamides versus Prolinamides in Organocatalyzed Aldol Reactions — A Comparative Study
Authors: Gryko Dorota , Chrominski Mikolaj , Pielacinska Dominika J.
Published: November 2011

Review: 48 refs.
ChemInform Abstract: Targeting Nucleic Acids Using Dynamic Combinatorial Chemistry
Authors: Sherman Durai Chandramathi R. , Harding Margaret M.
Published: November 2011

Review: 58 refs.
ChemInform Abstract: Asymmetric Organocatalytic Reactions of α,β‐Unsaturated Cyclic Ketones
Authors: Dalpozzo Renato , Bartoli Giuseppe , Bencivenni Giorgio
Published: November 2011

Review: 104 refs.
ChemInform Abstract: Hydrogen Bonded Arylamide Foldamers: From Conformational Control to Functional Evolution
Authors: Li Zhanting
Published: November 2011

Review: 75 refs.
ChemInform Abstract: Bioinspired Organic Chemistry
Authors: Tomas Salvador
Published: November 2011

Review: 117 refs.
ChemInform Abstract: Computational Organic Chemistry
Authors: Bachrach Steven M.
Published: November 2011

Review: 59 refs.
Gas Phase Synthesis of Core‐Shell Particles by the Example of TiO2 Nanoparticles with Conductive Shell
Authors: Poller Benjamin , Efimov Konstantin , Feldhoff Armin , Binnewies Michael
Published: November 2011

Ein neuartiges Verfahren zur Herstellung von Kern/Mantel‐Partikeln aus der Gasphase ermöglicht die Synthese und Ummantelung eines TiO2‐Partikelkerns mit einer elektrisch leitfähigen Hülle eines transparenten Oxids in einem Reaktor. Die Ummantelung der TiO2‐Partikel erfolgte mit fluordotiertem (SnO2:F) und antimondotiertem Zinn(IV)‐oxid (SnO2:Sb). Die Kern/Mantel‐Partikel wiesen eine spezifische Leitfähigkeit von bis zu 8 · 10–3 S cm–1 auf. Durch Variation von Prozessparametern können Dotierungsgrad und die elektrische Leitfähigkeit der Mantelschichten auf einfache Weise modifiziert werden.
Platinum(II) Phenanthroimidazoles for Targeting Telomeric G‐Quadruplexes
Authors: Castor Katherine J. , Mancini Johanna , Fakhoury Johans , Weill Nathanael , Kieltyka Roxanne , Englebienne Pablo , Avakyan Nicole , Mittermaier Anthony , Autexier Chantal , Moitessier Nicolas , Sleiman Hanadi F.
Published: November 2011

A rationally designed progression of phenanthroimidazole platinum(II) complexes were examined for their ability to target telomere‐derived intramolecular G‐quadruplex DNA. Through the use of circular dichroism, fluorescence displacement assays, and molecular modeling we show that these complexes template and stabilize G‐quadruplexes from sequences based on the human telomeric repeat (TTAGGG)n. The greatest stabilization was observed for the p‐chlorophenyl derivative 6 (G4DC50=0.31 μM). We also show that the G‐quadruplex binding complexes are able to inhibit telomerase activity through a modified telomerase repeat amplification protocol (TRAP‐LIG assay). Preliminary cell studies show that complex 6 is preferentially cytotoxic toward cancer over normal cell lines, indicating its potential use in cancer therapy.
An analytical performance model considering access strategy of an opportunistic spectrum sharing system
Authors: Tang Wanbin , Yu Huogen , Han Yanfeng , Li Shaoqian
Published: November 2011

In an opportunistic spectrum sharing system, secondary users (SUs) opportunistically access the white space spectrum that is not occupied by the primary user (PU). Some analytical performance models have been available based on Markov chain modeling. In these models, SUs and PUs access the spectrum by randomly selecting the available channels with equal probability. However, how SUs and PUs use the spectrum are controlled by the access strategy designed in their MAC layer in an ad‐hoc network or centralized radio resource management layer in an infrastructure‐based network. To analyze the grade of service (GoS) of the secondary system under consideration for the access strategy, we propose an access rule transition matrix to model the access behavior of radio resource management, and apply it into the continuous‐time Markov chain model. It was proved that the proposed model is equivalent to the original models assuming the random access strategy by simulation. Moreover, we analyzed the GoS performance of the secondary system by assuming an ordered hunt access strategy. The results showed that the GoS performance of secondary systems can be improved greatly if it knows the spectrum access strategy of the primary system. Copyright © 2011 John Wiley & Sons, Ltd.
Self‐Assembly of Linear and Cyclic Siloxane‐Containing Mesogens: Investigation of Layered Structures in Bulk and Thin Films
Authors: Heinz Paul , Hindelang Konrad , Golosova Anastasia , Papadakis Christine M. , Rieger Bernhard
Published: November 2011

Silicon‐containing materials which possess the ability to form mesophases are promising systems for applications in the fields of electro‐optical devices, nonlinear optics, and information storage media. In this work, the formation of supramolecular assemblies of a series of low molecular weight siloxane‐containing mesogens is presented. Besides a novel synthesis route via RuII‐catalyzed hydrosilylation of phenyl acetylene derivatives, mesophase characterization by modern analysis techniques is performed. As linker groups, leading to bi‐ and tetramesogens, linear disiloxane and cyclic tetrasiloxane are utilized. In the resulting class of materials, high thermal stability, induced by the formation of layered smectic‐type structures, is predominant. The smectic‐type phases were found to be monotropic. Layer distances in the assemblies, as well as the phase transition temperatures, can be controlled by the substitution motif on the mesogens (number and length of alkyl chains). In spin‐cast thin films, the layered domains are visualized by atomic force microscopy; furthermore, domain dimensions and electron densities are determined by grazing‐incidence small‐angle X‐ray scattering.
Accurate Bond Energies of Hydrocarbons from Complete Basis Set Extrapolated Multi‐Reference Singles and Doubles Configuration Interaction
Authors: Oyeyemi Victor B. , Pavone Michele , Carter Emily A.
Published: November 2011

Quantum chemistry has become one of the most reliable tools for characterizing the thermochemical underpinnings of reactions, such as bond dissociation energies (BDEs). The accurate prediction of these particular properties (BDEs) are challenging for ab initio methods based on perturbative corrections or coupled cluster expansions of the single‐determinant Hartree–Fock wave function: the processes of bond breaking and forming are inherently multi‐configurational and require an accurate description of non‐dynamical electron correlation. To this end, we present a systematic ab initio approach for computing BDEs that is based on three components: 1) multi‐reference single and double excitation configuration interaction (MRSDCI) for the electronic energies; 2) a two‐parameter scheme for extrapolating MRSDCI energies to the complete basis set limit; and 3) DFT‐B3LYP calculations of minimum‐energy structures and vibrational frequencies to account for zero point energy and thermal corrections. We validated our methodology against a set of reliable experimental BDE values of CC and CH bonds of hydrocarbons. The goal of chemical accuracy is achieved, on average, without applying any empirical corrections to the MRSDCI electronic energies. We then use this composite scheme to make predictions of BDEs in a large number of hydrocarbon molecules for which there are no experimental data, so as to provide needed thermochemical estimates for fuel molecules.
Major congenital malformations in women with gestational diabetes mellitus: a systematic review and meta‐analysis
Authors: Balsells Montserrat , García‐Patterson Apolonia , Gich Ignasi , Corcoy Rosa
Published: November 2011

Background

The risk of major congenital malformations (MCM) is increased in women with pregestational diabetes mellitus (PGDM). Whether this risk is increased in gestational diabetes mellitus (GDM) is still debated. The aim of this study was to perform a systematic review (and meta‐analysis) of major congenital malformations in women with gestational diabetes versus a reference population.

Methods

We conducted a MEDLINE search (1 January 1995 to 31 December 2009) of original studies reporting data on major congenital malformations in women with gestational diabetes and a reference group. Information on pregestational diabetes was collected when available. Two investigators considered studies for inclusion and extracted data; discrepancies were solved by consensus. Meta‐analysis tools were used to summarize results. MOOSE and PRISMA guidelines were followed.

Results

Two case control and 15 cohort studies were selected out of 3488 retrieved abstracts. A higher risk of major congenital malformations was observed in offspring of women with gestational diabetes with the following relative risk (RR)/odds ratios (OR) and 95% confidence intervals (CI): RR 1.16 (1.07–1.25) in cohort studies and OR 1.4 (1.22–1.62) in case control studies. Risk of major congenital malformations was much higher in offspring of women with PGDM than in those of the reference group: RR 2.66 (2.04–3.47) in cohort studies and OR 4.7 (3.01–6.95) in the single case control study providing information.

Conclusion

There is a slightly higher risk of major congenital malformations in women with gestational diabetes than in the reference group. The contribution of women with overt hyperglycemia and other factors could not be ascertained. This risk, however, is much lower than in women with pregestational diabetes. Copyright © 2011 John Wiley & Sons, Ltd.
Electronic, Steric, and Ligand Influence on the Solid‐State Structures of Substituted Sodium and Potassium Anilides
Authors: Glock Carsten , Görls Helmar , Westerhausen Matthias
Published: October 2011

Alkali metal amides are widely used as starting materials in salt metathesis and metalation reactions. N‐Substituted anilides (phenylamides) of sodium and potassium AN(Ph)R [A = Na, K; R = methyl (Me), isopropyl (iPr), phenyl (Ph)] are accessible by transamination with AN(SiMe3)2. Neutral coligands, such as ethers and amines, have a strong influence on the solid‐state structures and solubility in common organic solvents. The crystal structures of the following anilides are discussed: [(pmdta)KNPh2]2 (1) (pmdta = N,N,N′,N″,N″‐pentamethyldiethylenetriamine), [(pmdta)KN(Ph)iPr]2 (2), [(thf)2NaNPh2]2 (3) (thf = tetrahydrofuran), [(dme)NaN(Ph)iPr]2 (4) (dme = 1,2‐dimethoxyethane), [(pmdta)NaNPh2]2 (5), [(thf)2NaN(Ph)iPr]2 (6), [(tmeda)NaN(Ph)iPr]2 (7) (tmeda = N,N,N′,N′‐tetramethylethylenediamine), [(dme)2KN(Ph)iPr]2 (8), [(diox)1.33NaNPh2]∞ (9) (diox = 1,4‐dioxane), [(diox)NaN(Ph)iPr]∞ (10), [KN(Ph)Me]∞ (11), [{(thf)KN(Ph)iPr}5]∞ (12), [{(thf)KN(Ph)iPr}2·2KN(Ph)iPr] (13), and [(dme)0.25KN(Ph)iPr]∞ (14). All of the sodium anilides contain a central four‐membered Na2N2 ring, whereas the interactions between the cations and the π‐systems of the phenyl groups have an increased importance in the potassium derivatives. Bidentate ether bases such as diox and dme can act as bridging ligands; however, this coordination behavior was not observed for the multidentate amines tmeda and pmdta.
Unusual Reactivity of Dimethylsulfoxonium Methylide with Esters
Authors: Leggio Antonella , De Marco Rosaria , Perri Francesca , Spinella Mariagiovanna , Liguori Angelo
Published: November 2011

The dimethylsulfoxonium methylide was treated with esters under mild conditions to rapidly afford the corresponding carboxylic acids at room temperature. Moreover, by performing the procedure on enantiopure substrates, it was demonstrated that the reaction occurs without racemization. 18O‐labeled reagents showed that the reaction does not proceed through an ester hydrolysis mechanism. The reactions are characterized by an unusual reactivity of the dimethylsulfoxonium methylide. This methodology is general and can be considered a valid alternate route for ester cleavage when a substrate is sensitive to hydrolysis conditions.