双核钼铁硫簇合物[Fe(2, 2''-联吡啶3)][(S2MoS2FeCl2]的合成与晶体结构

双核Mo-Fe-S原子簇配合物[Fe(2,2′-bpy)₃][S₂MoS₂FeCl₂],是(Et₄N)₂MoS₄、FeCl₂和2,2′-联吡啶在乙腈中反应得到的结晶化合物.晶体属单斜晶系,空间群P2₁/c;a=9.328(3),b=26.788(2),c=13.764(3)Å;β=95.38(3)°;V=3424.2(11)ų;Z=4;D_c=1.698g/cm³;F(000)=1752.晶体结构用直按法解出;经全矩阵最小二乘法修正,最后R=0.068,R_ω=0.071(3933个I>3(σ)(I)的独立衍射).在晶体结构中配位阴离子[S₂MoS₂FeCl₂]^2-是排布在阳离子[Fe(2,2′-bpy)₃]²⁺所形成的空腔中.它是以非统计分布的形式存在,从而较准确地测定了各项键参数.Mo…Fe距离为2.773(2)Å,Mo-S_b和Fe-S_b有大致相等的键长.     

Interaction of 1-tert-perfluorobutyl-3,3-di(perfluoromethyl)-2-aziridinone with weak nucleophiles

The title perfluoro--lactam (1) was found to react with N,N-dimethylformamide to give initially a betaine (2) which undergoes ring enlargement to produce the isomeric 2-dimethylamino-3,4,4-tri(perfluoroalkyl)substituted 5-oxazolidone (3). Related betaines were also obtained on reaction of1 with pyridine, quinoline, benzalaniline, andp-dimethylaminobenzaldehyde.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 372–374, February, 1993.     

A reaction of 6-bromo-1,2-naphthoquinone with tri(<Emphasis Type="Italic">n</Emphasis>-butyl)phosphine: A convenient route to phosphorus-containing 1,2-naphthoquinones and 1,2-dihydroxynaphthalenes

A reaction of 6-bromo-1,2-naphthoquinone with tri(n-butyl)phosphine gave 2-hydroxy-4-tri(n-butyl)phosphonionaphth-1-olate (betaine with the P—C bond). When treated with bromine, this betaine changed into (6-bromo-1,2-dihydroxy-4-naphthyl)tri(n-butyl)phosphonium bromide and (6-bromo-1,2-dioxo-1,2-dihydro-4-naphthyl)tri(n-butyl)phosphonium bromide in the ratio ∼1: 1. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 534–536, March, 2007.     

三邻氯苄基和三邻氟苄基锡吡咯烷氨荒酸酯的合成及晶体结构

Tri(o-chlorbenzyl)tin dithiotetrahydropyrrolocarbamate 1 and tri(o-fluorbenzyl)tin dithiotetrahydropyrrolocar-bamate 2 were synthesized. Their structures were characterized by elementary analysis， IR and ¹H NMR and the crystal structures were determined by X-ray single crystal diffraction. The crystal 1 belongs to triclinic with space group ， a=0.9076(4)nm， b=1.0663(5)nm， c=1.5193(7)nm， α=75.811(6)°，β=89.344(6)°， γ=72.665(6)°， Z=2， V=1.3577(11)nm³， D_c=1.569g·cm^-3， μ=1.406mm^-1， F(000)=644， R=0.0282， wR=0.0617. The crystal 2 belongs to monoclinic with space group P2₁/c， a=1.355(2)nm， b=1.0143(16)nm， c=1.986(3)nm， β=109.94(2)°， Z=4， V=2.565(7)nm³， D_c=1.539g·cm^-3， μ=1.195mm^-1，F(000)=1200， R=0.0467， wR=0.0788. In the crystals of 1 and 2， the structures consist of discrete molecules containing five-coordinate tin atom in a distorted trigonal bipyramidal configuration. CCDC: 1， 213679; 2， 213680.     

三(邻溴苄基)溴化锡和四(对溴苄基)锡的合成及结构研究

邻溴苄基溴或对溴苄基溴与锡反应合成三(邻溴苄基)溴化锡(1)和四(对溴苄基)锡(2).经X射线方法测定了新化合物的晶体结构.晶体结构1属斜方六面体晶系,空间群为R-3,晶体学参数:a=1.3389(3) nm, b=1.3389(3) nm, c=2.1896(8) nm, V=3.3993(16) nm3, Z=6, Dx=2.077 Mg·m-3, μ(Mo Kα)=81.83 cm-1, F(000)=2004, R1=0.0477, wR2=0.1372;晶体结构2属正交晶系,空间群为Fdd2,晶体学参数:a=2.1027(7) nm, b=2.3034(8) nm, c=1.1431(4) nm, V=5. 536(3) nm3, Z=8, Dx=1.917 Mg·m-3, μ(Mo Kα)=67.11 cm-1, F(000)=3056, R1=0.0358, wR2=0.0659.化合物1中Sn-C键长为0.2160(8) nm, Sn-Br键长为0.2491(3) nm;化合物2中Sn-C键长分别为0.2175和0.2178 nm.中心锡与亚甲基碳(或溴)原子构成畸型四面体.     

Relationship between morphology structure and composition of polycaprolactone/Poly(ethylene oxide)/Polylactide copolymeric microspheres

A novel tri‐component copolymer, polycaprolactone/poly(ethylene oxide)/polylactide (PCEL) was synthesized. The effect of the chemical composition on physical properties was investigated by using NMR, differential scanning calorimetry (DSC) and X‐ray diffraction. Both the soft segment poly(ethylene oxide) (PEO) and polycaprolactone (PCL) could enhance the mobility of polymer chains and decrease the crystallizability of the copolymers. The polymeric microspheres, which are of interest for drug delivery systems, were prepared using an emulsification‐solvent evaporation technique. By scanning electron microscopy (SEM) and atomic force microscopy (AFM), the surface morphology of the microspheres was studied. It was found that the presence of PEO segment could improve the hydrophilicity of the copolymers and the morphology of the polymeric microspheres could be altered by adjusting the chemical composition. The accumulation of PEO segments on the outer surface of the polymeric microspheres was proven by X‐ray photoelectron spectroscopy (XPS). It had also been proven that the PCL segment could facilitate the movement of PEO segment to the outer surface. Copyright © 2002 John Wiley & Sons, Ltd.     

三(对氟苄基)氯化锡和三(对氟苄基)锡N,N-(1,4-亚丁基)氨荒酸酯的合成及晶体结构

合成了三(对氟苄基)氯化锡(1)和三(对氟苄基)锡N,N-(1,4-亚丁基)氨荒酸酯(2).通过元素分析、红外光谱和核磁共振氢谱对其结构进行了表征.用X射线单晶衍射测定了这两个化合物的晶体结构.化合物1为单斜晶系,空间群P21, a=0.8403(3) nm, b=0.5958(2) nm, c=2.0016(8) nm, β=97.052(6)°, Z=2, V=0.9945(7) nm3, Dc=1.608 g/cm3, μ=1.447 mm-1, R1=0.0397, wR2=0.0813.化合物2为单斜晶系,空间群P21/n, a=0.8786(9) nm, b=1.993(2) nm, c=1.5039(15) nm, β=103.548(15)°, Z=4, V=2.560(4) nm3, Dc=1.537 g/cm3, μ=1.197 mm-1, R1=0.0363, wR2=0.0796. 在1的晶体中,锡原子呈四配位畸变四面体构型;2的晶体中,锡原子则是五配位畸变三角双锥构型.     

Theoretical study of two C30H20 isomers with a dodecahedrane cage and two pentaprismane cages sharing two pentagons

Structures, energies, and vibrational frequencies have been calculated for two C₃₀H₂₀ isomers with a dodecahedrane cage and two pentaprismane cages at the B3LYP/6‐31G* level of theory. Thus, two C₃₀H₂₀ isomers have the form of coplanar tri‐cage molecules. The symmetry of one C₃₀H₂₀ isomer is of D_5d and that of another is of C_2V. The heat of formation for two C₃₀H₂₀ isomers have been estimated. Heats of formation of two C₃₀H₂₀ isomers as well as the vibrational analysis indicate that two C₃₀H₂₀ isomers enjoy sufficient stability to allow for its experimental preparation. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005     

The physical and NMR characterizations of allyl‐ and crotylcelluloses

Tri‐O‐allylcellulose (degree of polymerization, DP ∼112) was prepared in ∼91% yield, and tri‐O‐crotylcellulose (DP ∼138) was prepared in ∼56% yield from microcrystalline cellulose (DP ∼172, and polydispersity index, PDI ∼1.95) using modified literature methods. Number‐average molecular weight (M_n = 31,600), weight‐average molecular weight (M_w = 191,800), and PDI = 6.07 data suggested that tri‐O‐allylcellulose may be crosslinking in air to generate branched chains. The polymer was stabilized with 100 ppm butylated hydroxy toluene (BHT). The material without BHT experienced glass transition (T_g, differential‐scanning calorimetry, DSC) between −2 and +3 °C, crosslinked beyond 100 °C, and degraded at 298.6 °C (by thermogravimetric analysis, TGA). M_n (45,100), M_w (118,200), PDI (2.62), and thermal data (T_g − 5 to +3 °C, melting point 185.8 °C, recrystallization 168.9 °C, and degradation 343.6 °C) on tri‐O‐crotylcellulose suggested that the polymer was formed with about the same polydispersity as the starting material and is heat stable. While allylcellulose generated continuous flexible yellow films by solution casting, crotylcellulose precipitated from solution as brittle white flakes. Dynamic mechanical analysis (DMA) data on allylcellulose films (T_g − 29.1 °C, Young's modulus 5.81 × 10⁸ Pa) suggest that the material is tough and flexible at room temperature. All ¹H and ¹³C resonances in the NMR spectra were identified and assigned using the following methods: Double‐quantum filter correlation spectroscopy (DQF COSY) was used to assign the network of seven protons in the anhydroglucose portion of the repeat unit. The proton assignments were verified and confirmed by total correlation spectroscopy (TOCSY). A combination of heteronuclear single‐quantum coherence (HSQC) and ¹³C spectroscopies were used to identify all bonded carbon–hydrogen pairs in the anhydroglucose portion of the repeat unit, and assign the carbon nuclei chemical shift values. Heteronuclear multiple bond correlation (HMBC) spectroscopy was used to connect the resonances of methines and methylenes at positions 2, 3, and 6 to the methylene resonances of the allyl ethers. TOCSY was used again to identify the fifteen ¹H resonances in the three pendant allyl groups. Finally, a combination of HSQC, HMBC, and ¹³C spectroscopies were used to identify each carbon in the allyl pendants at 2, 3, and 6. Because of line broadening and signal overlap, we were unable to identify the conformational arrangement about the C5 and C6 bond in tri‐O‐allyl‐ and tri‐O‐crotylcelluloses. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1889–1902, 2000     

Synthesis and Molecular Structure of Binuclear Organotin Complex Bridged by Piperazinylbidithiocarbamate Anion

1 INTRODUCTION In recent years, the organotin dithiocarba- mates have been extensively studied due to their biological activities[1～6]; while to our knowledge, polynuclear complexes consisting of multidithiocar- bamatlic acids and alkyltin(IV) have not …