第五、六族元素的有机化合物在有机合成中应用的研究 ⅩⅦ.胂叶立德与氟代烯烃的反应

氰基亚甲基-(1b)、苯甲酰基亚甲基-(1c)及乙酰基亚甲基-苯基胂(1d)分别与全氟丙烯反应,生成氰基-2,3,3,3-四氟丙酰基亚甲基-三苯基胂(4b)、苯甲酰基-(3c)及乙酰基-[反式全氟丙烯-1]基亚甲基三苯基胂(3d)。3c,3d分别经湿苯回流后转化为苯甲酰基-(4c)及乙酰基-2,3,3,3-四氟丙酰基亚甲基三苯基胂(4d)。甲氧羰基亚甲基三苯基膦(1e)与全氟丙烯也能发生类似的反应,可是苯甲酰基-及乙酰基-亚甲基三苯基膦在相似的反应条件下与全氟丙烯不反应。甲氧羰基亚甲基三苯基胂(1a)与三氟氯乙烯反应,生成低产率的甲氧羰基氟氯代乙酰基亚甲基三苯基胂(4f)。其反应残渣用甲醇处理后,得到的产物为二氟三苯基胂(7)和氟氯代乙酸甲酯(8)。     

第五、六族元素的有机化合物在有机合成中应用的研究

ⅩⅫ.胂叶立德与氟代烯烃的反应 氰基-(1b)、苯甲酰基-(1c)及乙酰基亚甲基-三苯基胂(1d)分别与全氟丙烯反应,生成氰基-2,3,3,3-四氟丙酰基亚甲基-三苯基胂(4b)、苯甲酰基-(3c)及乙酰基-[反式全氟丙烯-1]基亚甲基三苯基胂(3d)。(3c),(3d)分别经湿苯回流后转化为苯甲酰基-(4c)及乙酰基-2,3,3,3-四氟丙     

经由胂叶立德立体有择合成仿保幼激素──增丝素（ZR－512）及其（2Z，4E）－异构体

３－甲基－２－丁烯酸乙酯４经ＳｅＯ２反式氧化、还原、溴化得到关键中间体４－溴－３－甲基－（２Ｅ）－丁烯酸乙酯７．７与三苯基胂反应生成季８．二氢香茅醛与８在Ｋ＿２ＣＯ＿３－乙醇－微量水的存在下反应，得到（２Ｅ，４Ｅ）－３，７，１１－三甲基－２，４－十二碳二烯酸乙酯１ａ及其（２Ｚ，４Ｅ）－异构体１ｂ，产率７４％。该反应具有（４Ｅ）－立体选择性，同时Ｃ－２双键发生部分构型转化。     

经由胂叶立德立体有择合成仿保幼激素──增丝素（ZR—512）…

３－甲基－２－丁烯酸乙酯４经ＳｅＯ２反式氧化，还原，溴化得到关键中间体４－溴－３－甲基－（２Ｅ）－丁烯酸乙酯７．７与三苯基胂反应生成季Ｓｅｎｇ盐８。二氢香茅醛与８在Ｋ２ＣＯ３－乙醇－微量水的存在下反应，得到（２Ｅ，４Ｅ）－３，７，１１－三甲基－２，４－十二碳二烯酸乙酯１ａ及其（２Ｚ，４Ｅ）－异构体１ｂ，产率７４％，该反应具有（４Ｅ）－立体选择性，同时Ｃ－２双键发生部分构型转化。     

Abnormal Reaction of 1-(2′-Methoxybenzoyl)-1-(2′-hydroxy-5′-methoxycarbonylbenzoyl)methane Treated with Etyyl Orthoformate and Acetic Anhydride

邻羟基二苯甲酰基甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应通常是ＨＣ（ＯＥｔ）３作为酰化剂，得到３－苯甲酰基色酮。本文报道５－甲氧羰基－２－羟基苯甲酰基－（２′－甲氧苯甲酰基）甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应时，是Ａｃ２Ｏ而不是ＨＣ（ＯＥｔ）３作为酰化剂，生成３－苯甲酰基－２－甲基色酮。其结构经ＮＭＲ、ＭＳ、ＩＲ和ＥＡ证实。并对其反应机理作了讨论。     

用色谱-质谱和质量色谱研究苯甲酸钐热分解反应

为合成某些芳香族有机化合物提供一种新途径，用色谱－质谱联用技术和质量色谱法研究了苯甲酸钐的热分解反应产物。其热分解产物溶入丙酮后有大量９，１０－蒽醌析出，其丙酮溶液中还含有１，２－二苯甲酰基苯（２５６％）、苯甲酸（１８７％）、二苯酮（１４４％）、９－芴酮（８２％）、９－苯基芴（４９％）、联苯（３６％）、二苯甲烷（２３％）、３－甲酰苯基联苯（２１％）、二苯基乙二酮（１９％）、４－甲酰苯基联苯（１８％）、芴（１７％）、ｍ－二苯甲酰基苯（１１％）和ｐ－二苯甲酰基苯（０２％）等５５种化合物。讨论了苯甲酸盐的热分解反应机理。     

1—（5‘—甲氧羰基—2’—羟基苯甲酰基（—1—（2‘—甲氧苯甲酰基）甲烷与Ac2O和HC...

邻羟基二苯甲酰基甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）３反应通常是ＨＣ（ＯＥｔ）３作为酰化剂，得到３－苯甲酰基色酮。本文报道５－甲氧羰基－２－羟基苯甲酰基－（２＇－甲氧苯甲酰基）甲烷与Ａｃ２Ｏ和ＨＣ（ＯＥｔ）ｓ反应时，是Ａｃ２Ｏ而不是ＨＣ（ＯＥｔ）作为酰化剂，生成３－苯甲酰基－２－甲基色酮。其结构经ＮＭＲ、ＭＳ、ＩＲ和ＥＡ证实。并对其反应机理作了讨论。     

膦、胂叶立德的化学应用与应用（XXIX）：——含全氟烷基胂叶立德水解合成2—吡喃酮衍生物

在无水碳酸钾存在下，以无水二氯甲烷作溶剂，室温下将溴化（2－萘甲酰基）甲基三苯基Shen（1）与2－全氟炔酸甲酯（2）反应，高产率地得到加合产物4－（2－萘甲酰基）－2－三苯基胂基－3－全氟烷基－3－丁烯酸甲酯（3）和少量4－（2－萘甲酰基）－4－三苯基胂基－3－全氟烷基－2－丁烯酸甲酯（4），加合产物3在9：1的甲醇－水溶液中在一定温度下反应，高产率地得到4－全氟烷基－6－（2－萘基）－2－吡喃酮（5），研究发现硅胶对该反应具有催化作用，提出并讨论了反应机理。     

2,3,4,5-四取代-顺-2,3-二氢呋喃立体选择性合成方法的研究

研究了3种合成2甲氧羰基3芳基4乙酰基5甲基顺2,3二氢呋喃(7)的方法.方法1:用甲氧羰基亚甲基三苯基胂(5)与3(取代苯甲叉)2,4戊二酮(6)反应;方法2:用溴化甲氧羰基甲基三苯基胂(4)在碳酸钾存在下与戊二酮6反应;方法3(分步一锅法):三苯基胂(2)与溴代乙酸甲酯(3)加热反应,生成的产物不经分离,冷却至室温,加入碳酸钾和6继续反应.     

取代邻羟基二苯甲酮的合成1,3,5-三甲氧基苯与对位取代苯甲酰氯的Friedel-Crafts反应

控制反应物摩尔比、反应温度和反应时间，１，３，５－三甲氧基苯与对位取代苯甲酰氯发生Ｆｒｉｅｄｅｌ－Ｃｒａｆｔｓ反应，选择性地合成了２－羟基－４，６－二甲氧基－４－Ｒ－二苯甲酮和３－（４″－Ｒ－苯甲酰基）－２－羟基－４，６－二甲氧基－４－Ｒ－二苯甲酮。反应条件温和，产率较高。化合物的结构都经元素分析、１ＨＮＭＲ和ＩＲ确定。     

Complexation of UVI with 1-hydroxyethane-1,1-diphosphonic acid in acidic to basic solutions

Complexation of UVI with 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) in acidic to basic solutions has been studied with multiple techniques. A number of 1:1 (UO2H3L), 1:2 (UO2HjL2 where j = +4, +3, +2, +1, 0, and -1), and 2:2 [(UO2)2HjL2 where j = +1, 0, and -1] complexes form, but the 1:2 complexes are the major species in a wide pH range. Thermodynamic parameters (formation constants and enthalpy and entropy of complexation) were determined by potentiometry and calorimetry. Data indicate that the complexation of UVI with HEDPA is exothermic, favored by the enthalpy of complexation. This is in contrast to the complexation of UVI with dicarboxylic acids in which the enthalpy term usually is unfavorable. Results from electrospray ionization mass spectrometry and 31P NMR have confirmed the presence of 1:1, 1:2, and 2:2 UVIHEDPA complexes.     

Synthesis and reduction of 2,2-diaryl-1-nitroethylenes by using a chiral and a non chiral NADH model in the pyrrolopyridine series

Reduction of 2,2-diphenyl-1-nitroethylene ( 1 ) and 2-(2-pyridyl)-2-phenyl-1-nitroethylene ( 5 ) is achieved by using the NADH model in the pyrrolopyridine series 2a to give 2,2-diphenyl-1-nitroethane ( 3 ) and 2-(2-pyridyl)-2-phenyl-1-nitroethane ( 7 ) respectively in 40% yield. The asymmetric reduction of 2-(2-pyridyl)-2-phenyl-1-nitroethylene by the chiral NADH model 2b is studied. Thus, 2-(2-pyridyl)-2-phenyl-1-nitroethane ( 7 ) is obtained in 15 to 32% yield. The stereocontrol of the reduction proved to be dependent on the amount of magnesium ions.     

Ceometries,Energetics and Spectroscopic Properties of Oxygen Clusters Oxy (x=2～6, y=-2～2)

The geometries, energetics and spectroscopic properties of oxygen clusters, Oxy(x=2~6, y=-2~2), were investigated at the B3LYP/6-311G (d, p) level. The CASSCF calculations were carried out for the ground and excited states of3O2and2O2+. The total energy is3O2(3Σg-)<2O2-(2Πgi)<1O2(1Δg)<1O2-2(1Σg+)<2O2+(2Πg)<1O2+2(1Σg+). The relative energy of the active doublet anion of oxygen molecule,2O2-(2Πgi), is only 28 kJ/mol higher than the triplet neutral oxygen molecule,3O2(3Σg-). The calculated O-O vibrational frequencies all are in good agreement with the experimental values. They are 1577 (1580), 1139 (1090), 1563 (1484), 627 (615~545) and 1993 (1905) cm-1, where the O-O vibrational frequency values in parentheses are experimental values, for3O2(3Σg-),2O2-(2Πgi),1O2(1Δg),1O2-2(1Σg+) and2O2+(2Πg), respectively. Moreover, the O-O vibrational frequency of1O2+2(1Σg+) was computed as 2368 cm-1which has not been reported before at both experimental and theoretical levels. Both bent and linear geometries of O3were studied. The bent-types of O3are more favorable than the linear-type in energy. Three types of structure for oxygen trimers are calculated at the B3LYP/6-311G (d, p) level. They are the structure-I with an obtuse angle of O-O-O,the structure-II with an acute angle of O-O-O, and the structure-III of linear type. For a bent-type structure of O3species (structure-I), the total enegy is2O3-(2B1)<1O3(1A1)<3O3(3B2)<1O3-2(1A1)<2O3+(2A1). The optimization of geometry at B3LYP/6-311G (d, p) level indicated that the species of2O3-(2B1) with 1.3573 of O-O bond length and 115.6584o of O-O-O bond anger is the ground state of O3. The total energy of O4species and their ions is2O4-(Cs,2A′, bend-type)<2O4-(C2v,2A2,face-centered triangle-type)<2O4-(D∞h,2Σg, linear-type)<1O4(Cs,1A′, bend-type)<1O4(D∞h,1Σg, linear-type)<1O4(D4h,1A1g, square-type)<1O4(C2v,1A1, face-centered triangle-type)<2O4-(D4h,1A1g, square-type)<2O4+(D∞h,2Σg, linear-type)<2O4+(Cs,1A′, bend-type). The species with the lowest relative energy is an anion,2O4-(Cs,2A′, bendtype), with chair form geometry and characteristic vibronic frequencies of 1179 and 1349 cm-1. The relative energy of1O5(C2v,1A1) with coplanar-triangle-bicone geometry is the lowest among the O5species and their ions, which may be a resonance structure with1O5(C2v,1A1) of A type. Their characteristic vibronic frequency is 1302 cm-1. The relative energy of the O6species and their ions with hexagon geometry is lower than one with linear geometry. Their infrared vi-bronic intensity may be weak and unobservable but the Raman vibronic intensity may be strong and observable based on their symmetry.     

New insights in the formation of thioxophosphine: a quantum chemical study

The investigation of the thioxophosphine (PS) formation from different reaction paths is successfully performed and presented in this paper. The PH(3)+SH(1) reaction is likely to yield the intermediates PH(2) (2)+H(2)S through an energy barrier of 2.8 kcal mol(-1). However, the next step is the H(2)PS(2) formation, which has a too high energy barrier, 52.6 kcal mol(-1). The PH(3)+S(1) reaction path is the likely source of the HPS(1) molecule. The other possibilities are the PH(1)+H(2)S, PH(2) (2)+SH(1), and PH(3)+H(2)S reactions, but they are spin forbidden and energetically unfavorable for the HPS(1) and PSH(1) formations. On the other hand, the PS(2) formation is more likely to happen by the PH(1)+SH(1) reaction. The PH(2) (2)+S(1), PH(3)+SH(1), P(2)+H(2)S, and P(4)+H(2)S reactions are also favorable in terms of energetics; however, these reactions are spin forbidden. The chemical mechanism for the PS(2) formation is now presented in more details, which is of great importance in the atmosphere of Jupiter and Saturn, and in interstellar medium.     

Solid-state and solution-state coordination chemistry of the zinc triad with the mixed N,S donor ligand bis(2-methylpyridyl) sulfide

The binding of group 12 metal ions to bis(2-methylpyridyl) sulfide (1) was investigated by X-ray crystallography and NMR. Seven structures of the chloride and perchlorate salts of Hg(II), Cd(II), and Zn(II) with 1 are reported. Hg(1)(2)(ClO(4))(2), Cd(1)(2)(ClO(4))(2), and Zn(1)(2)(ClO(4))(2).CH(3)CN form mononuclear, six-coordinate species in the solid state with 1 binding in a tridentate coordination mode. Hg(1)(2)(ClO(4))(2) has a distorted trigonal prismatic coordination geometry while Cd(1)(2)(ClO(4))(2) and Zn(1)(2)(ClO(4))(2).CH(3)CN have distorted octahedral geometries. With chloride anions, the 1:1 metal to ligand complexes Hg(1)Cl(2), [Cd(1)Cl(2)](2), and Zn(1)Cl(2) are formed. A bidentate binding mode that lacks thioether coordination is observed for 1 in the four-coordinate, distorted tetrahedral complexes Zn(1)Cl(2) and Hg(1)Cl(2). [Cd(1)Cl(2)](2) is dimeric with a distorted octahedral coordination geometry and a tridentate 1. Hg(1)Cl(2) is comprised of pairs of loosely associated monomers and Zn(1)Cl(2) is monomeric. In addition, Hg(2)(1)Cl(4) is formed with alternating chloride and thioether bridges. The distorted square pyramidal Hg(II) centers result in a supramolecular zigzagging chain in the solid state. The solution (1)H NMR spectra of [Hg(1)(2)](2+) and [Hg(1)(NCCH(3))(x)()](2+) reveal (3)(-)(5)J((199)Hg(1)H) due to slow ligand exchange found in these thioether complexes. Implications for use of Hg(II) as a metallobioprobe are discussed.     

Criegee中间体气相反应热力学的G2理论计算

Criegee intermediate is believed to play an important role in the atmospheric chemistry. Because of its short life and the difficulty in experimental study, we carried out ah initio calculations on the thermochemistry of the Criegee involving reactions in this study. Thermochemistry data of reaction enthalpies and Gibbs free energies for four different stable structures of the Criegee intermediates (singlet CH2OO ①1 A1 in C2v, triplet CH2OO ②3B1 in C2v, singlet CH2OO ③1A' in Cs and triplet CH2OO ④ in C1 symmetry) involved in some of the gas-phase reactions were calculated at the standard Gaussian-2 [G2(MP2) and G2] and a modified G2, G2(fu1)[10],levels of theory. Relative energies among those Criegees and formic acid were compared. Chemical reactions include the formation of Criegees, re-arrangement from Criegee to formic acid, dissociations (producing CH2(3B1)+O2, CH2(1A1)+O2, CO2+H2, CO2+2H, CO+H2O, OH+HCO) and the reactions between Criegee and NO/H2O. Standard equilibrium constants for some reactions were investigated and may be obtained for all of the rest reactions involved in this study by the standard Gibbs free energies. It is shown that the formation of Criegee ①-④ by ethylene and ozone, the re-arrangement from any Criegee to formic acid, the dissociation in producing CO2+O2and CO+H2O and the reactions between any Criegee and NO/H2O are all favourable thermodynamicaly. The dissociation in forming CO2+2H and OH+HCO is less favourable. While the dissociation in forming carbene (either in 3B1 or 1A1 state) is not allowed by ΔrGm? values. Standard enthalpies of formation at 298 K for the four Criegees were predicted at the G2(ful) level of theory. Each value is the average value from ten of the above reactions and they are -4.3, 74.8,98.9 and 244.6 kJ mol-1 at the G2(ful) level for Criegee ① to Criegee ④, respectively. In addition, tile standard enthalpy of formation at 298 K for HOCH2OOH is further predicted to be -315.6 kJ mol-1 at the G2(MP2) level.     

1H-1H dipolar couplings provide a unique probe of RNA backbone structure

A NMR method is described that permits simultaneous measurement of the geminal 2JH1H2 + 2DH1H2 splitting and the sum of the 1JCH1 + 1DCH1 + 1JCH2 + 1DCH2 couplings for methylene groups, where 2DH1H2 and 1DCH are residual dipolar couplings, occurring when molecules are weakly oriented relative to the magnetic field. By suppressing either the upfield or downfield half of the 1H-1H geminal doublet, the experiment yields improved resolution relative to regular two-dimensional 1H-13C correlation spectra, making it applicable to systems of considerable complexity. The method is demonstrated for measurement of all 2DH5'H5' couplings in a 24-nucleotide 13C-enriched RNA stem loop structure, weakly aligned in liquid crystalline Pf1. The method is equally applicable to methylene groups in 13C-labeled proteins and to natural abundance samples of smaller molecules.     

Chemo- and periselectivity in the addition of [OsO2(CH2)2] to ethylene: a theoretical study

Quantum chemical calculations by using density functional theory at the B3LYP level have been carried out to elucidate the reaction course for the addition of ethylene to [OsO2(CH2)2] (1). The calculations predict that the kinetically most favorable reaction proceeds with an activation barrier of 8.1 kcal mol(-1) via [3+2] addition across the O=Os=CH2 moiety. This reaction is -42.4 kcal mol(-1) exothermic. Alternatively, the [3+2] addition to the H2C=Os=CH2 fragment of 1 leads to the most stable addition product 4 (-72.7 kcal mol(-1)), yet this process has a higher activation barrier (13.0 kcal mol(-1)). The [3+2] addition to the O=Os=O fragment yielding 2 is kinetically (27.5 kcal mol(-1)) and thermodynamically (-7.0 kcal mol(-1)) the least favorable [3+2] reaction. The formal [2+2] addition to the Os=O and Os=CH2 double bonds proceeds by initial rearrangement of 1 to the metallaoxirane 1 a. The rearrangement 1-->1 a and the following [2+2] additions have significantly higher activation barriers (>30 kcal mol(-1)) than the [3+2] reactions. Another isomer of 1 is the dioxoosmacyclopropane 1 b, which is 56.2 kcal mol(-1) lower in energy than 1. The activation barrier for the 1-->1 b isomerization is 15.7 kcal mol(-1). The calculations predict that there are no energetically favorable addition reactions of ethylene with 1 b. The isomeric form 1 c containing a peroxo group is too high in energy to be relevant for the reaction course. The accuracy of the B3LYP results is corroborated by high level post-HF CCSD(T) calculations for a subset of species.     

1H NMR analysis of the tolylene-2,4-diisocyanate – methanol reaction

<正>Tolylene-2,4-diisocyanate(2,4-TDI) 1 reacts with methanol through two simultaneous paths in the polyurethane reaction,which involve two different intermediates-tolylene-4-carbamatic-2-isocyanate 2 and tolylene-2-carbamatic-4-isocyanate 3,and the final product is tolylene-2,4-dicarbamate 4.The-CH_3 chemical shifts in benzene ring in compounds 1,2,3 and 4 can be easily tested and well distinguished,through which those four compounds are quantified and their kinetics are investigated.It shows that four rate constants for the tolylene-2,4-diisocyanate-methanol reaction in CCl_4 at 50℃are k_1=9.6×10~(-2)h~(-2)mol~(-2)min~(-1), k_2=1.4×10~(-2)h~(-2)mol~(-2)min~(-1),k_3=4.0×10~(-3)h~(-2)mol~(-2)min~(-1),k_4=1.4×10~(-3)h~(-2)mol~(-2)min~(-1).(k_1 is the reaction rate constant from compounds 1 to 2;k_2 is the reaction rate constant from compounds 1 to 3;k_3 is the reaction rate constant from compounds 3 to 4;k_4 is the reaction rate constant from compounds 2 to 4).     

Interpretation of light-scattering spectra in terms of particle displacements

Quasielastic light-scattering spectroscopy is regularly used to examine the dynamics of dilute solutions of diffusing mesoscopic probe particles in fluids. For probes in a simple liquid, the light-scattering spectrum is a simple exponential; the field correlation function g(1)(q,tau) of the scattering particles is related to their mean-square displacements X2 identical with [(delta x(tau))2] during tau via g(1)(q,tau) = exp(-1/2 q2X2). However, demonstrations of this expression refer only to identical Brownian particles in simple liquids and show that if the form is correct then it is also true for all tau that g(1)(q,tau) = exp(-gamma tau), a pure exponential in tau. In general, g(1)(q,tau) is not a single exponential in time. A correct general form for g(1)(q,tau) in terms of the X(2n), replacing the incorrect exp(-1/2 q2X2), is obtained. A simple experimental diagnostic determining when the field correlation function gives the mean-square displacement is identified, namely, g(1)(q,tau) only reveals X2 if g(1)(q,tau) is a single exponential in tau. Contrariwise, if g(1)(q,tau) is not a single exponential, then g(1)(q,tau) depends not only on X2 but on all higher moments X(2n). Corrections to the crude approximation g(1)(q,tau) = exp(-1/2 q2X2) closely resemble the higher spectral cumulants from a cumulant expansion of g(1)(q,tau).