不对称合成中的手性膦(磷)酸酯(酰胺)催化剂

讨论了手性膦(磷)酰胺及膦(磷)酸酯催化剂在不对称烷基化、不对称缩合、不对称氢化、不对称氰硅化等反应中应用的最新研究进展。参考文献48篇。     

烃基膦酸单十六烷基酯的结构与其萃取镱(Ⅲ)、镥(Ⅲ)性能的关系

探讨了一类具有高位阻特征的烃基膦酸单十六烷基酯萃取剂R1(R2O)P(O)OH从氯化物介质中萃取Yb(Ⅲ)和Lu(Ⅲ)的结构与性能关系.其中,R1分别为CH2,C2H5,i-C3H7,cyclo-C3H11和C6H5,R2为C4H9CH(C2H5)C2H4CH(C6H13)或C6H13CH(CH3)CH2CH(C6H13).结果表明,这类萃取剂对于Yb,Lu的萃取和分离能力随着其分子中取代基空间位阻的增大而降低.     

高位阻有机磷萃取剂的研究——Ⅰ.烃基膦酸单十六烷基酯的合成及其对钴(Ⅱ)、镍(Ⅱ)等金属离子的萃取性能

合成了6个具有高位阻特征的烃基膦酸单十六烷基酯萃取剂,并考察了它们对Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、Fe(Ⅲ)和Ca的萃取性能。萃取剂分子中烃基结构的变化对各种金属离子的萃取能力有着不同程度的影响。空间位阻较大的异丙基和环己基化合物具有比2-乙基己基膦酸单2-乙基己基酯(P507)更高的Co-Ni分离能力。     

烷基磷(膦)酸酯~(31)P NMR的取代基效应

本文利用分子力学计算,将核磁共振中烷基取代基效应的Van der Waal模型扩展到磷酸三烷基酯、烷基膦破二烷基酯、二烷基膦酸烷基酯和三烷基氧化膦。在各类磷化合物中,δ~(31)P和E_(vdw·p)之间存在有良好线性关系。此外,还用分子力学计算方法和变温核磁共振谱方法探讨了一系列烷基膦酸O,O-1,3-亚丙酯和烷基膦酸O,O-1,4-亚丁酯的构型平衡。在气相和非极性溶剂中,前者以烷基处于平键的椅式构型存在,后者以烷基处于平键的扭船式构型存在。     

O-烷基S-烷基(芳基)硫代磷(膦)酸衍生物与三氯氧磷的氯化反应──合成S-烷基(芳基)硫代磷(膦)酰氯酯的新方法

在研究O,O二烷基O芳基硫代磷酸酯(1)与三氯氧磷的异构化氯化反应机理时,发现1的异构化产物O,S二烷基硫代磷酸酯(4)能顺利地与三氯氧磷反应,4中的烷氧基被氯原子取代,得到的产物S烷基硫代磷酰氯酯(2)和O烷基磷酰二氯酯3.当4中的R为烷基或苯基,R'为烷氧基、芳氧基、烷硫基、芳硫基、二烷基氨基、氮杂环基、苯基和甲基,R"为C_1-4烷基时,4的氯化反应也能顺利发生,并得到较高产率的预期产物.     

手性亚膦（磷）酸联二萘酚（胺）酯配体的应用研究

本文综述了手性亚膦（磷）酸联二萘酚酯及手性亚膦（磷）酸联二萘酚胺酯配体在不对称催化应用中的最新进性。     

某些酸性磷(膦)酸酯-Co(Ⅱ)、Ni(Ⅱ)、VO(Ⅱ)配合物的电子光谱和ESR波谱

本文对某些酸性磷(膦)酸酯与Co(Ⅱ)、Ni(Ⅱ)、VO(Ⅱ)配合物的电子光谱进行了测定,讨论了这类配合物的构型和光谱参数对萃取性能的影响。实验测得并计算了VO(Ⅱ)配合物的ESR波谱参数和键参数,对这类配合物的成键特性进行了讨论。     

O,O-二烷基硫代磷(膦)酸酯与三氯氧磷的异构化/氯化反应机理初探

O,O－二烷基硫代磷(膦)酸酯(1)与三氯氧磷作用得到S-烷基硫代磷酰氯(2)和O-烷基磷酰二氯(3),此反应包含异构化和氧化两个过程.实验结果表明,1的预期氯化产物O-烷基硫代磷(膦)酰氯酯(5)与三氯氧磷不发生反应,而1的预期异构化产物O,S-二烷基硫代磷(膦)酸酯(6)与三氯氧磷能顺利反应得到2.由此推测,在1的异构化/氯化反应中,异构化很可能发生在氯化之前.根据此结果和三角双锥中间体(TBP)概念,提出了该反应初步的可能机理.     

二甲基胺取代-烃基膦酸树脂对钆(Ⅲ)的吸附性能

用二甲基胺取代 烃基膦酸树脂对钆的吸附行为进行研究,试验结果表明,在pH4.90时,树脂对钆的静态饱和吸附容量为219mg·g-1(树脂);用2mol·L-1HCl可以定量洗脱;表观吸附速率常数k298=1.81×10-4s-1,测得吸附热力学参数分别为:ΔH=77.46kJ·mol-1,ΔG=-32.417kJ·mol-1,ΔS=368.69J·mol-1·K-1;等温吸附服从Frenndlich曲线;树脂功能基与Gd(Ⅲ)的配位比为2∶1;并用红外光谱探讨了树脂与钆的成键情况。     

Methylene chloride chemical ionization of fumaric and maleic acids and their esters

The chemical ionization (CI) mass spectrometry of fumaric and maleic acids and their esters with methylene chloride as reagent gas is described. The introduction of methylene chloride to the CI(CH₄) plasma led to the formation of new characteristic ions in addition to the protonation and the subsequent fragmentation, revealing diagnostic information on the configuration of geometrical isomers. The new characteristic ions have been found to arise from the addition of the reactant ion of methylene chloride, [CH₂Cl]⁺, to the substrates and, for higher dialkyl esters, from the further McLafferty rearrangement of the adduct ion [M + CH₂Cl]⁺.     

Identification tree based on fragmentation rules for structure elucidation of organophosphorus esters by electrospray mass spectrometry

Organophosphorus compounds have played important roles as pesticides, chemical warfare agents and extractors of radioactive material. Structural elucidation of phosphonates poses a particular challenge because their initial forms can be hydrolyzed, thus, degradation products may predominate in samples acquired in the field. The analysis of non‐volatile organophosphorus compounds and their degradation products is possible using electrospray tandem mass spectrometry ESI‐MS/MS. Here, we present a generic strategy that allows the unambiguous identification of substituents for two families of organophosphorus compounds: the phosphonates and phosphates. General fragmentation rules were deduced based on the study of decomposition pathways of 55 organophosphorus esters, including examples found in the literature. Multistage MS (MSⁿ) experiments at high resolution in a hybrid mass spectrometer provide accurate mass measurements, whereas collision‐induced dissociation experiments in a triple quadrupole give access to small fragment ions. The creation of a specific nomenclature for each possible structure of organophosphorus compound, depending on the alkyl side chain linked to the oxygen, was achieved by applying these fragmentation rules. This led to the creation of an ‘identification tree’ based upon the unique consecutive decomposition pathways uncovered for each individual compound. Hence, seven structural motifs were created that orient an unequivocal identification using the ‘identification tree’. Despite the similar structures of the ensemble of phosphate and phosphonate esters, distinct identifications based upon characteristic neutral losses and diagnostic fragment ions were possible in all cases. Copyright © 2013 John Wiley & Sons, Ltd.     

Polynitroalkyl esters of ONN-azoxycarboxylic acids

Polyhitroethylurethanes react smoothly with various nitroso compounds in the presence of dibromoisocyanurate to give polynitroalkyl esters of ONN-azoxycarboxylic acids in a yield of 55–95%.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1660–1663, July, 1992.     

Long-acting androgens: Analytical and preparative HPLC of testosterone esters

Procedures are described for the normal phase and reverse phase HPLC analysis of testosterone esters having diverse side chains: examples are given of the gram-scale purification of these compounds using two commercial preparative liquid chromatography and an economical and efficient laboratory-assembled preparative liquid chromatograph.     

Relation between chemical structure of amino acids and their thermal decomposition

The influence of substituents on the thermal decomposition of monomeric organic compounds was studied. For this purpose the thermal destruction of dozen or so α-amino acids of the diversified chemical constitution, among others compounds containing the second amine group, additional carboxyl group, amino acids containing hydroxyl or sulfhydryl groups and amino acids connected with five-member heterocyclic ring or existing in the form of hydrates or hydrochlorides were investigated. The analyses were performed using a derivatograph in an air atmosphere, sample sizes were from 50 to 200 mg and heating rate from 3 to 15 K min^-1. It has been established that the thermal decomposition of studied compounds occurs in three stages. The temperature ranges, in which the analyzed compounds undergo thermal transformations were established. For evaluation of the thermoanalytical results an advanced multivariate data processing method, principal component analysis (PCA), was used. By this method the influence of the specific functional groups on the thermal decomposition of α-amino acids was determined. The stage of decomposition, in which the thermoanalytic data are the best correlated to the chemical constitution of the compound, is the second stage. It has also been recognized, that better discrimination among the analyzed compounds was obtained for the data set of the DTA.     

Synthesis of aminooxyphosphonic acids and their esters

Conclusions The Arbuzov reaction and alkylation by -haloalkylphosphonic esters gave diesters of aminooxymethane-, -aminooxyethane-, and -aminooxybutanephosphonic acids; aminooxymethane- and -aminooxyethanephosphonic acids; and monoesters of -aminooxyethanephosphonic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1202–1204, May, 1986.