bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Correlation of 113Cd NMR and 111mCd PAC Spectroscopies Provides a Powerful Approach for the Characterization of the Structure of CdII‐Substituted ZnII Proteins
Authors: Iranzo Olga , Jakusch Tamas , Lee Kyung‐Hoon , Hemmingsen Lars , Pecoraro Vincent L. 
Published: February 2009

AbstractThe powerful combination of 113Cd NMR and 111mCd PAC (perturbed angular correlation) spectroscopies has been critical to determine the coordination geometry of CdII bound to thiolate‐rich centers. We have obtained important linear correlations between 113Cd NMR and 111mCd PAC spectroscopic data and the acid/base properties of the metal binding site that illustrate the presence of a dynamic model for metal binding (see figure). These unique results can give new insight into CdII‐substituted ZnII proteins.magnified imageCdII has been used as a probe of zinc metalloenzymes and proteins because of the spectroscopic silence of ZnII. One of the most commonly used spectroscopic techniques is 113Cd NMR; however, in recent years 111mCd Perturbed Angular Correlation spectroscopy (111mCd PAC) has also been shown to provide useful structural, speciation and dynamics information on CdII complexes and biomolecules. In this article, we show how the joint use of 113Cd NMR and 111mCd PAC spectroscopies can provide detailed information about the CdII environment in thiolate‐rich proteins. Specifically we show that the 113Cd NMR chemical shifts observed for CdII in the designed TRI series (TRI=Ac‐G(LKALEEK)4G‐NH2) of peptides vary depending on the proportion of trigonal planar CdS3 and pseudotetrahedral CdS3O species present in the equilibrium mixture. PAC spectra are able to quantify these mixtures. When one compares the chemical shift range for these peptides (from δ=570 to 700 ppm), it is observed that CdS3 species have δ 675–700 ppm, CdS3O complexes fall in the range δ 570–600 ppm and mixtures of these forms fall linearly between these extremes. If one then determines the pKa2 values for CdII complexation [pKa2 is for the reaction Cd[(peptide−H)2(peptide)]+→Cd(peptide)3− + 2H+] and compares these to the observed chemical shift for the Cd(peptide)3− complexes, one finds that there is also a direct linear correlation. Thus, by determining the chemical shift value of these species, one can directly assess the metal‐binding affinity of the construct. This illustrates how proteins may be able to fine tune metal‐binding affinity by destabilizing one metallospecies with respect to another. More important, these studies demonstrate that one may have a broad 113Cd NMR chemical shift range for a chemical species (e.g., CdS3O) which is not necessarily a reflection of the structural diversity within such a four‐coordinate species, but rather a consequence of a fast exchange equilibrium between two related species (e.g., CdS3O and CdS3). This could lead to reinterpretation of the assignments of cadmium–protein complexes and may impact the application of CdII as a probe of ZnII sites in biology.
Acceleration of Reductive Elimination of [Ar‐Pd‐C] by a Phosphine/Electron‐Deficient Olefin Ligand: A Kinetic Investigation
Authors: Zhang Heng , Luo Xiancai , Wongkhan Kittiya , Duan Hui , Li Qiang , Zhu Lizheng , Wang Jian , Batsanov Andrei S. , Howard Judith A. K. , Marder Todd B. , Lei Aiwen 
Published: February 2009

AbstractDramatic rate enhancement of reductive elimination of [Ar‐Pd‐C] was observed in the presence of a phosphine/electron‐deficient olefin ligand. Through systematic kinetic investigations of the Negishi coupling of ethyl 2‐iodobenzoate with alkylzinc chlorides (see scheme), the rate constants for reductive elimination of [Ar‐Pd‐C] were determined to be greater than 0.3 s−1, which is about four or five orders of magnitude greater than values reported previously.magnified imageThe kinetics of the reductive elimination step of a CC Negishi cross‐coupling catalyzed by a 1:1 complex 2 of palladium and the phosphine/electron‐deficient olefin ligand (E)‐3‐(2‐diphenylphosphanylphenyl)‐1‐phenyl‐propenone (1) was studied. Complex 2 is an exceptionally efficient and highly selective catalyst for Negishi cross‐coupling reactions involving primary and secondary alkylzinc reagents bearing β‐hydrogen atoms. Turnover numbers (TONs) as high as 105 and turnover frequencies (TOFs) as high as 1000 s−1 were observed. The reactions occurred rapidly and selectively even at 0 °C. The fact that the reaction was first order in [Pd] is consistent with homogeneous catalysis by Pd complexes rather than by Pd nanoparticles (NPs). Through systematic kinetic investigations of the Negishi coupling of ethyl 2‐iodobenzoate with alkylzinc chlorides, the rate constants for reductive elimination of [Ar‐Pd‐C] were determined to be >0.3 s−1, which is about 4 or 5 orders of magnitude greater than the values previously reported for [Pd(dppbz)] and [Pd(PPh3)2] systems (dppbz=1,2‐bis(diphenylphosphino)benzene). The use of a 2:1 ratio of 1:Pd resulted in reduced catalytic activity and selectivity, presumably because the olefin moiety could no longer assist in the reductive elimination step. Importantly, hydrogenation of the CC double bond in ligand 1 generated a saturated ligand (1H2), which was not only less effective than 1, but also gave rise to substantial amount of ethylbenzoate formed by competing β‐hydride elimination. Thus, the π‐accepting olefin moiety in 1 must enhance reductive elimination rates, and, consequently, inhibit formation of byproducts resulting from β‐hydride elimination.
Asymmetric Friedel–Crafts Reaction of 4,7‐Dihydroindoles with Nitroolefins by Chiral Brønsted Acids under Low Catalyst Loading
Authors: Sheng Yi‐Fei , Li Gong‐Qiang , Kang Qiang , Zhang An‐Jiang , You Shu‐Li 
Published: February 2009

AbstractSlowly does it! By adding the substrate by a syringe pump, a highly efficient Friedel–Crafts reaction of 4,7‐dihydroindoles with nitroolefins was realized with 0.5 mol % of a chiral phosphoric acid. The Friedel–Crafts alkylation, together with a subsequent oxidation of the product, led to 2‐substituted indoles in excellent enantiomeric excesses, which can be easily transformed to enantioenriched tetrahydro‐γ‐carbolines.magnified image
Controlling the Chair Conformation of a Mannopyranose in a Large‐Amplitude [2]Rotaxane Molecular Machine
Authors: Coutrot Frédéric , Busseron Eric 
Published: February 2009

AbstractMolecular machines boarding now! Molecular machines containing dibenzo[24]crown‐8 (DB24C8) and based on an anilinium and a pyridinium amide station have been prepared. The DB24C8 shuttles upon variation of pH and interacts differently with the pyridinium amide station depending on its substitution. When the DB24C8 sits around the disubstituted amide, the conformation of the pyranose changes from 1C4 to 4C1.magnified image
Synthesis of Spiroheterocycles by Palladium‐Catalyzed Domino Cycloisomerization/Cross‐Coupling of α‐Allenols and Baylis–Hillman Acetates
Authors: Alcaide Benito , Almendros Pedro , Martínez del Campo Teresa , Quirós M. Teresa 
Published: February 2009

AbstractFirst insights into the reaction between a Baylis–Hillman adduct and an allene moiety have been obtained from the novel domino heterocyclization/cross‐coupling reaction of α‐allenols and Baylis–Hillman acetates, which furnishes [(2,5‐dihydrofuran‐3‐yl)methyl]acrylate derivatives in moderate to good yields.magnified image
Gold‐Catalyzed [4C+3C] Intramolecular Cycloaddition of Allenedienes: Synthetic Potential and Mechanistic Implications
Authors: Trillo Beatriz , López Fernando , Montserrat Sergi , Ujaque Gregori , Castedo Luis , Lledós Agustí , Mascareñas Jose L. 
Published: February 2009

AbstractEfficient at room temperature: The Au complex generated in situ from [(IPr)AuCl] and AgSbF6 promotes the [4C+3C] intramolecular cycloaddition of allenes and dienes at room temperature, and in a particularly efficient and versatile manner. A DFT study on dimethylallenyl precursors agreed with the formation and cycloaddition of a metal–allyl cation intermediate, and points to the 1,2‐hydride shift as the key rate‐limiting step.magnified image
ChemInform Abstract: Predicted Energies and Structures Associated with the Mixed Calcium Strontium Fluorapatites
Authors: Michie Emily M. , Grimes Robin W. , Fong Shirley K. , Metcalfe Brian L. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Magnetism and Electronic Structure of YbNi2‐xFexAl8 (x = 0.91) Isolated from Al Flux.
Authors: Wu Xiuni , Francisco Melanie , Rak Zsolt , Bakas T. , Mahanti S. D. , Kanatzidis Mercouri G. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solvothermal Synthesis of Two Cationic Indium Selenides with I‐ Ion as Counterion.
Authors: Li Chun‐Ying , Zhou Jian , Zhang Yong , Lei Zhi‐Xin , Bian Guo‐Qing , Dai Jie 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Nanocrystalline LnBO3 (Ln: Y, Nd, Sm, Eu, Gd, Ho) and YBO3:Eu Using a Borohydride‐Based Solution Precursor Route.
Authors: Henkes Amanda E. , Schaak Raymond E. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Crystal Structure, and Property of One‐ and Two‐Dimensional Complexes Based on Paradodecatungstate‐B Cluster.
Authors: Li Bao , Bi Lihua , Li Wen , Wu Lixin 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Nitriles and Carbonyl Groups as Acceptors in Titanocene‐Catalyzed Radical Cyclizations.
Authors: Gansaeuer Andreas , Piestert Frederik , Huth Inga , Lauterbach Thorsten 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Nanocrystalline Magnesium Oxide‐Stabilized Molybdenum: An Efficient Heterogeneous Catalyst for the Aerobic Oxidation of Alcohols to Carbonyl Compounds.
Authors: Kantam M. Lakshmi , Yadav Jagjit , Laha Soumi , Sreedhar Bojja , Bhargava Suresh 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Total Synthesis of Isoindolobenzazepine Alkaloids, Lennoxamine (XV) and Chilenine (XVI), Based on Palladium‐Catalyzed Reduction of Alkenyl Phosphates.
Authors: Fuwa Haruhiko , Sasaki Makoto 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Pyrazoles, Diazepines, Enaminones, and Enamino Esters Using 12‐Tungstophosphoric Acid as a Reusable Catalyst in Water.
Authors: Chen Xiang , She Jin , Shang Zhicai , Wu Jun , Wu Haifeng , Zhang Peizhi 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Use of D‐Mannitol‐Derived C2‐Symmetric Trienes in Tandem Metathesis Reactions Towards Valuable Lactones.
Authors: Riache Nassima , Blond Alain , Nay Bastien 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Chemoselective Etherification of Benzyl Alcohols Using 2,4,6‐Trichloro‐1,3,5‐triazine and Methanol or Ethanol Catalyzed by Dimethyl Sulfoxide.
Authors: Sun Lili , Guo Yuping , Peng Guisheng , Li Chunbao 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Palladium‐ and Nickel‐Catalyzed Cross‐Couplings of Unsaturated Halides Bearing Relatively Acidic Protons with Organozinc Reagents.
Authors: Manolikakes Georg , Munoz Hernandez Carmen , Schade Matthias A. , Metzger Albrecht , Knochel Paul 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Reaction Control in the Organocatalytic Asymmetric One‐Pot, Three‐Component Reaction of Aldehydes, Diethyl α‐Aminomalonate and Nitroalkenes: Toward Diversity‐Oriented Synthesis.
Authors: Liu Yan‐Kai , Liu Hao , Du Wei , Yue Lei , Chen Ying‐Chun 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Convenient General Asymmetric Synthesis of Roche Ester Derivatives Through Catalytic Asymmetric Hydrogenation: Steric and Electronic Effects of Ligands.
Authors: Pautigny Cyrielle , Jeulin Severine , Ayad Tahar , Zhang Zhaoguo , Genet Jean‐Pierre , Ratovelomanana‐Vidal Virginie 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Indium(I) Bromide Promoted Stereoselective Preparation of Cyclopropanes via Sequential Aldol‐Type Coupling/Elimination/Michael‐Induced Ring Closure Reaction from α,α‐Dichloroacetophenone and Aldehydes.
Authors: Peppe Clovis , das Chagas Rafael Pavao , Burrow Robert Alan 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient Stereoselective Synthesis of Nitrocyclopropanes by the Oxidative Cyclization of Michael Adducts of Nitroolefins with Activated Methylene Compounds.
Authors: Fan Renhua , Ye Yang , Li Weixun , Wang Lingfei 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Magnesium—Cadmium Chloride, a Bimetallic Catalyst System for the Allylation of Aldehydes with Allyl Bromide: An Efficient Protocol for the Synthesis of Homoallylic Alcohols
Authors: Narsaiah A. Venkat , Reddy A. Ramesh , Rao Y. Gopala , Kumar E. Vijay , Prakasham R. S. , Reddy Basi V. Subba , Yadav Jhillu S. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Silver‐Catalyzed, Manganese‐Mediated Allylation and Benzylation Reactions of Aldehydes and Ketones.
Authors: Barczak Nicholas T. , Jarvo Elizabeth R. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Nickel‐Catalyzed Reductive Carboxylation of Styrenes Using CO2.
Authors: Williams Catherine M. , Johnson Jeffrey B. , Rovis Tomislav 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Suzuki—Miyaura Coupling Reaction of Boronic Acids and Ethyl Glyoxylate: Synthetic Access to Mandelate Derivatives.
Authors: Francesco Irene Notar , Wagner Alain , Colobert Francoise 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solvent‐Free Synthesis of α‐Aminonitriles from Aldehydes, Amines and Trimethylsilyl Cyanide Catalyzed by Thallium(III) Chloride Tetrahydrate.
Authors: Majhi Anjoy , Kim Sung Soo , Kadam Santoshi T. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Unsymmetrical Biaryls by Palladium‐Catalyzed Coupling of Aryl Halides with Internal Reduction.
Authors: Satyanarayana Gedu , Maier Martin E. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of Chiral (Sulfinyl)furyl Oxazoline Ligands and Application to Enantioselective Palladium‐Catalyzed Allylic Alkylation.
Authors: Bunya Yusuke , Sengoku Takaaki , Imamura Yoko , Arai Yoshitsugu 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ligand‐Free Iron/Copper Cocatalyzed Alkynylation Coupling Reactions.
Authors: Mao Jincheng , Xie Guanlei , Wu Minyan , Guo Jun , Ji Shunjun 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Cross‐Coupling Reactions of Aryl Pivalates with Boronic Acids.
Authors: Quasdorf Kyle W. , Tian Xia , Garg Neil K. 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Polymer‐Supported Sulfonic Acid Catalyzed Three‐Component One‐Pot Synthesis of α‐Amidoalkyl‐β‐naphthols.
Authors: An Li‐Tao , Lu Xiao‐Hua , Ding Fei‐Qing , Jiang Wen‐Qing , Zou Jian‐Ping 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Development of Bifunctional Acyclic Hydroxyl‐guanidine Organocatalyst: Application to Asymmetric Nucleophilic Epoxidation.
Authors: Shin Bongki , Tanaka Shinji , Kita Tetsuya , Hashimoto Yuichi , Nagasawa Kazuno 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Chiral Organosulfur Catalyst for Highly Stereoselective Synthesis of Epoxides.
Authors: Gui Yuan , Li Jian , Guo Chang‐Shan , Li Xin‐Liang , Lu Zhi‐Feng , Huang Zhi‐Zhen 
Published: February 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.