67~(th) Meeting of the Israel Chemical Society

Topics: Charge- Transfer Reactions, Nanochemistry and Single Molecules, Stereochemistry andAssymmetric Synthesis, Bioinorganic and Bioorganic Chemistry, Enzymes and Proteins, Quantum Chemistry, Chemistry Education, Thin Films and Supramolecular Chemistry, Colloid Chemistry, Recent Israeli Scientific Contributions, Analytical Chemistry, Industrial Chemistry and more.The conference will take place onJanuary 29-30, 2002At the Renaissance Hotel and Convention Center, Jerusalem, Isra…     

Sergei Vasil’evich Volkov (on the 70th Birthday)

Chronicle

Sergei Vasil’evich Volkov (on the 70th Birthday)     

Yurii Grigor’evich Papulov (On the 75th birthday)

Chronicle

Yurii Grigor’evich Papulov (On the 75th birthday)     

Kinetics and mechanism of the anation of (αβ)-hydroxo(tetraethylenepentamine)cobalt(III) by thiosulfate, the base hydrolysis of the (sulfur-bonded) thiosulfato(tetraethylenepentamine)-cobalt(III) and photochemistry of oxygen and sulfur-bonded thiosulfato complexes

Summary The reaction of ()-(tetren)CoOH²⁺ with S₂O ₃ ^2- in the 7.25–8.28 pH range at 20–40 °C yielded S- (yellow) and O- (purple) bonded thiosulfato(tetren)cobalt(III) complexes, the former in larger quantities. The rate determining step is preceded by diffusion-controlled ion-pair [(tetren)CoOH²⁺,S₂O ₃ ^2- ] formation. Replacement of coordinated OH^- by S₂O ₃ ^2- is interpreted in terms of an internal conjugate base mechanism: (tetren)CoOH²⁺ (tetren-H)CoOH ₂ ²⁺ , the reactive amido conjugate base being generated by intramolecular proton transfer from the coordinated NH site.In acid medium the S-bonded (tetren)Co(S₂O₃)⁺ is highly stable to redox decomposition, in contrast to its pentaammine analogue. The complex however, undergoes base hydrolysis yielding the corresponding hydroxo complex. The rate and activation parameters for the base hydrolysis have been reported. Photolysis of O- and S-bonded isomers of [(tetren)CoS₂O₃]⁺ in acidic medium at 254 and 313 nm, respectively, yielded aquation products accompanied by some decomposition of S₂O ₃ ^2- .     

Mechanism of the Deaquation of Aquopentaaminocobalt(III) Bromide

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｓｏｌｉｄ ｐｈａｓｅｄｅａｑｕａｔｉｏｎ ａｎａｔｉｏｎｒｅａｃｔｉｏｎ[Ｍ(ＮＨ3 ) 5(Ｈ2 Ｏ) ]Ｘ3 → [Ｍ(ＮＨ3 ) 5Ｘ]Ｘ2 +Ｈ2 Ｏ(Ｍ =Ｃｏ3 + ,Ｃｒ3 + ｏｒＲｕ3 + ａｎｄＸ =Ｃｌ- ,Ｂｒ- ｏｒＮＣＳ- )ｈａｓｂｅｅｎｗｉｄｅｌｙｓｔｕｄｉｅｄｓｉｎｃｅｔｈｅｎｉｎｅｔｅｅｎｓｉｘｔｉｅｓ .Ｔｈｅｔｈｅｒｍａｌａｎｄｋｉｎｅｔｉｃｐａｒａｍｅｔｅｒｓｈａｖｅｂｅｅｎｃａｌｃｕｌａｔｅｄａｎｄｔｈｅｄｉｆｆｅｒｅｎｔｍｅｃｈａｎｉｓｍｈａｓｂｅｅｎｐｒｏｐｏｓｅｄａｎｄｄ…     

Synthesis of the D-Galactopyranoside Derivative of C_(60)

ThefascinatingsbocturesandpropertiesoffullereneshaveoPeneduPanewfieldofchendstry.Inparticular,F.Wudletal.l'2haveshownthatwatersofubleC6ocomPoundsinhibittheHITVen-zymesprotease(HIVP)andreversetranscriPtase(HIVRT).IthasbeenafocusofstUdytoinvestigatethebiologicalactivitiesofthesenovelsubstances.Fortheirpossiblemedicaluses,tolinkC6omoleculetonaturalProductssuchassugars,pephdes,amioacides,andsoonisanimPortantmethodinthisfield.Vasella3reportedthefirstglucosidederivativeofC6o'InthispaPer,w…     

Cyclic structure of the β(γ)-hydroxy-(mercapto)alkylimines of aldoses

In solutions in DMSO-d₆, the products from the condensation of ethanolamine and 1,2- and 1,3-aminopropanols with aldoses are mixtures of the - and -pyranose forms, whereas the -mercaptoethylimines of aldoses have the 1,3-thiazolidine structure. Glucose -mercaptoethylimine is characterized by ring-chain tautomerism involving the -pyranose and diastereomeric 1,3-thiazolidine tautomers.Military-Medical Academy, St. Petersburg, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1068–1071, August, 1998.     

On the 75th birthday of Igor’ Aleksandrovich Tutorskii

Jubilees

On the 75th birthday of Igor’ Aleksandrovich Tutorskii     

Synthesis of (NHC)Rh(cod)Cl and (NHC)RhCl(CO)2 complexes – Translation of the Rh- into the Ir-scale for the electronic properties of NHC ligands

Twenty-three different Rh complexes of the (NHC)RhCl(cod) and (NHC)RhCl(CO)₂ type were synthesized from [RhCl(cod)]₂. The electron donating nature of the NHC ligands was changed in a systematic manner. The redox potentials of the various (NHC)RhCl(cod) and the ν(CO) of the various (NHC)RhCl(CO)₂ were determined. A correlation of the Rh redox potentials and the Rh ν(CO), respectively, with the related data from analogous (NHC)IrCl(cod) and (NHC)IrCl(CO)₂ complexes established two linear relationships. The linear regression (R² = 0.993) of the Rh and the Ir redox potentials results in an equation for the redox potential transformation: E_1/2(Ir) = 1.016 · E_1/2(Rh) ? 0.076 V. The linear regression (R² = 0.97) of the Rh and Ir ν_av(CO) results in an equation for the ν_av(CO) transformation: ν_av(CO)Ir = 0.8695 · ν_av(CO)Rh + 250.7 cm^?1. In this manner the Rh and the Ir-scale for the determination of the electron donating properties of NHC ligands are unified.     

Method of the selection of the g(α) function based on the reduced-time plot

A method for the selection of the g(α) function describing the thermal decomposition of solids based on the reduced-time plot is proposed. This method allows more objective selection of the g(α) function best describing the experimental results from a mathematical point of view, when compared to the graphical method applied up to the present. With the use of variously defined values of reduced time, this method was applied to the investigation of the kinetics of the isothermal decomposition of CaCO₃ under nitrogen. The listing of a computer program enabling the carrying out of calculations and the making of plots is given.     

Effects of Thermal Activation on the Electrocatalysis of the Ru(0001) Surface

ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｅｌｅｃｔｒｏｃｈｅｍｉｃａｌｏｘｉｄａｔｉｏｎｏｆｓｍａｌｌ,ｏｘｙ ｇｅｎａｔｅｄｏｒｇａｎｉｃｍｏｌｅｃｕｌｅｓｏｎ ｐｌａｔｉｎｕｍａｎｄｒｅｌａｔｅｄｅｌｅｃｔｒｏｄｅｍａｔｅｒｉａｌｓｈａｓｂｅｅｎｅｘｔｅｎｓｉｖｅｌｙｓｔｕｄｉｅｄｏｖｅｒｔｈｅｐａｓｔｔｈｒｅｅｄｅｃａｄｅｓ ,ｍａｉｎｌｙｉｎｓｕｐｐｏｒｔｏｆｆｕｅｌｃｅｌｌｒｅｓｅａｒｃｈｅｓ[1— 4 ] .Ｔｈｅｓｅｒｅａｃｔｉｏｎｓａｒｅｃｏｍｐｌｉｃａｔｅｄ ,ａｓｓｅｖｅｒａｌｅｌｅｍｅｎｔａｒｙｓ…     

To the 75th birthday of Igor Mstislavovich Barkalov (28 Sep. 1935–4 Jan. 2009)

Cronicle

To the 75th birthday of Igor Mstislavovich Barkalov (28 Sep. 1935–4 Jan. 2009)     

4~(th) East-Asian Polymer Conference

May 28~31, 2006 Tianjin, ChinaOrganized by Institute of Polymer Chemistry, College of Chemistry Nankai University Key Laboratory of Functional Polymer Materials (Nankai University), Ministry of Education Tianjin University of Science & Technology Editorial Office of Chinese Journal of Reactive Polymers Chinese Chemical Society, Polymer Division (CCS) Sponsored by National Natural Science Foundation of China (NSFC) TEDA GOLONE Chemical Co., Ltd Call for Papers Participan…     

Theoretical Study of the Thermal Decomposition of Chlorofluoromethanol (CHClFOH)

Introduction Hydrochlorofluorocarbons (HCFCs) have been widely used as replacements of chlorofluorcarbons (CFCs). The insertion of O (1D) into the CH bond of HCFC forms the activated alcohol. It has been shown that these hot alcohols play an important role in the degradation mechanism of atmospheric compounds1.Chlorofluoromethanol (CHClFOH) appears in the reaction of O (1D) with CH2ClF (HCFC-31)2. Neither experimental nor theoretical study of this species was available to date. U…     

Determination of the Absolute Configuration of the (−)-Me(EtO)(HO)P-Mo(CO)5 Coordination Complex by Decomplexation of the Organophosphorus Ligand

Abstract

The resolution of a chiral coordination complex (1) was recently carried out in our laboratory, and some stereochemical transformations of the resolved specie have been reported (L. P. Reiff, L. J. Szafraniec, D. I. Rossman and H. S. Aaron, Inorg. Chem. 1986, 25, 0000). Decomplexation studies of its organophosphorus ligand have now been carried out. Thus, treatment of the (?)-1 complex with two molar equivalents of triphenylphosphine yields (+)-ethyl methylphosphinate (2), considerably racemized, however, due to the 120°C temperature required to achieve decomplexation. To determine its optical purity and its absolute configuration, the latter was converted into the known S-(?)-3 thioic acid and S-(?)-4 methyl ester, respectively. While the method does not appear to be of synthetic utility for the preparation of optically active (decomplexed) organophosphorus species, the absolute configuration of the S-(?)-1 coordination complex is established on the basis of these stereochemical relationships.     

On the 70th birthday of Oleg Georgievich Us’yarov

Jubilee

On the 70th birthday of Oleg Georgievich Us’yarov     

On the 70th Birthday of Valerii Grigor’evich Kulichikhin

Jubilee

On the 70th Birthday of Valerii Grigor’evich Kulichikhin     

β-Cyclodextrin Facilitates the Cleavage of Cobalt-Carbon Bonds during the Electrochemical Reduction of Alkylaquabis(dimethylglyoximato)Cobalt(Ⅲ)

HomolysisoftheCo-CbondisakeystePincoempeB12dependentenZymecatalyticCycle[l].Howevr,whytheempmeacceleratestherateofCo-Cbondcleavage2lO1otimesisstillunknown[21.Therefre,effortShaVebeenmadeforinvestigahononalargenumberofcoempeBl2modelsencomPassingtheStrUctUreandfunchonrelahonshipforthecoeap'meBl2.ButmoStformerinVestigationsincludingtheelectrochendsnyweredoneontheisolatedcoempeB12oritSmodelsl3].Recenhy,therehasbeenanincreasingintereStinusingcyClodextrins(CDs)asaamcialempeduetoCDscanfOr…     

Congratulations to Professor Bao-tong Huang on the Occasion of His 80~(th) Birthday——Biographic Sketch of Professor Bao-tong Huang

Professor Bao-tong Huang (formerly known as Pao-tung Huang, Paul) of the Changchun Institute ofApplied Chemistry, Chinese Academy of Sciences was born in Shanghai on May 1~(st) 1921. He waseducated at the University of Shanghai (1940～1942) and the National Central University (1942-1944)and conferred the degree of B.S. in chemistry. He retried to Shanghai after the end of the war againstJapan. Prof. Huang undertook his graduate studies at the Texas A & M College (M.S. in Chemistry,