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1.
Nd(naph)3-Al(i-Bu)3催化马来酸酐和环氧丙烷交替聚合   总被引:3,自引:0,他引:3  
研究了马来酸酐和环氧丙烷的交替共聚,发现Nd(naph)3-Al(i-Bu)3是马来酸酐(MAn)和环氧丙烷(PO)交替共聚的良好催化剂,用红外光谱,核磁共振研究了共聚物的结构。共聚反应动力学研究表明共聚反应与单体和催化剂浓度均呈一级关系。表观活化能为11kj/mol.  相似文献   

2.
测定了三元体系La(ClO4)3-OCBAAP-H2O在30℃时的溶解度.结果表明,该体系有一个新固相(不一致溶解化合物)La(OCBAAP)4(ClO4)3·6H2O形成.参考该体系溶度图确定合成条件,合成了系列化合物Ln(OCBAAP)4(ClO4)3·nH2O(Ln=La,n=6;Ln=Pr,Nd,Sm,Gd,Yb,n=2).通过化学分析、元素分析、TG-DTG、IR和密度对化合物进行了表征,计算了La(OCBAAP)4(ClO4)3热分解过程各阶段的表观活化能.  相似文献   

3.
本文利用过渡金属的亲硫性,通过Cp*-W(CO)3Cl(Cp*=C5H5,C5H4CH3)与HFe2Co(CO)9(μ3-S)反应,得到四种含硫异核金属羰基原子簇化合物Cp*WFeCo(CO)8(μ3-S)(Cp*=C5H5,Ⅰ-a;Cp*=C5H4CH3,Ⅱ-a),(Cp*W)2Fe(CO)7(μ3-S)(Cp*=C5H5,Ⅰ-b;Cp*=C5H4CH3,Ⅱ-b)。对合成的簇合物进行了IR,1H/13C-NMR,C/H及金属分析,并对Ⅰ-a进行了X-射线单晶结构分析。  相似文献   

4.
Co3(CO)7(μ3—S)(μ,η^2—SCNR2)的合成和晶体结构   总被引:1,自引:0,他引:1  
Co2(CO)8与4个二硫代双(烷基硫代甲酰胺)类前配体[R2NC(S)S]2反应,得4个含烷基硫代甲酰胺基的三核钴羰基硫簇合物。通过元素分析、IR、^1HNMR和MS等方法表征了它们的结构,用X射线衍射法测定了其中一个簇合物Co3(CO)7(μ3-S)[μ,η^2-SCN(i-Pr)2](Ⅲ)的晶体结构。晶体属单斜晶系,P21/n空间群,晶胞参数a=1.1452(2)nm,b=1.5028(3)  相似文献   

5.
Co2(CO8)分别与4种硫代乙内酰脲S=CNHC(O)C(R1)(R2)N(COR3)反就,得到4个新的含硫代乙内酰脲桥基双齿配位的三核钴羰基硫族合物。用元素分析、IR、^1H NMR和MS等手段表征了它们的结构,用X射线衍射测定了其中一个族合物Co3(CO7)7(μ3-S)[μ,η^2-SCNC(O)C(CH3)(CH3)N(COCH3)](Ⅳ)的晶体结构,晶体属三斜晶系,P1↑-空间群,晶胞  相似文献   

6.
标题化合物C_(18)H_(17)N_2O_3PS是O-芳基苯基硫代膦酰肼与马来酸酐加成后的关环产物,其晶体属于单斜晶系,空间群P2_1/c,α=10.726(3),b=10.248(2),c=17.454(5)A, β=104.01(2)°,Mr=372.37,V=1861.4A3,Dc=1.33g/cm ̄3,Z=4,μ(CuKα)=24.68cm ̄(-1),F(000)=776,R=0.070,Rw=0.067。结构由直接法解出,分子中P原子与其相邻的S,O,N,C原子形成变形四面体构型。  相似文献   

7.
张欣  章丽娟 《结构化学》1996,15(6):491-494
标题化合物C_(18)H_(17)N_2O_3PS是O-芳基苯基硫代膦酰肼与马来酸酐加成后的关环产物,其晶体属于单斜晶系,空间群P2_1/c,α=10.726(3),b=10.248(2),c=17.454(5)A, β=104.01(2)°,Mr=372.37,V=1861.4A3,Dc=1.33g/cm ̄3,Z=4,μ(CuKα)=24.68cm ̄(-1),F(000)=776,R=0.070,Rw=0.067。结构由直接法解出,分子中P原子与其相邻的S,O,N,C原子形成变形四面体构型。  相似文献   

8.
Co2(CO8)分别与4种硫代乙内酰脲S=CNHC(O)C(R1)(R2)N(COR3)反应,得到4个新的含硫代乙内酰脲桥基双齿配位的三核钴羰基硫簇合物.用元素分析、IR、1HNMR和MS等手段表征了它们的结构,用X射线衍射测定了其中一个簇合物CO3(CO)7(μ3-S)[μ,η2-SCNC(O)C(CH3)(CH3)N(COCH3)](IV)的晶体结构,晶体属三斜晶系,P1空间群,晶胞参数:a=0.8456(3)nm,b=1.1534(3)nm,c=1.1990(4)nm;a=107.36(3)°,β=108.44(5)°,γ=90.18(3)°;V=1.052(6)nm3,Z=2,F(000)=584,Dc=1.86g/cm3,μ=25.71cm-1,最终偏离因子R=0.046,Rw=0.058.  相似文献   

9.
Fe(acac)3-Al(i-Bu)3对马来酸酐与茴香脑共聚的催化性能   总被引:6,自引:0,他引:6  
 研究了Fe(acac)3-Al(i-Bu)3(acac=乙酰丙酮)催化体系对马来酸酐(MA)与茴香脑(ANE)共聚反应的催化性能.动力学研究结果表明,MA与ANE共聚对单体的浓度呈一级反应,其表观活化能为31.0kJ/mol.用IR和13CNMR研究了共聚物的结构,结果表明聚合物是交替的,其中酸酐的含量为45.6%.用GPC测定了聚合物的分子量及其分布,结果表明分子量的分布较窄,PDI=1.19~1.42.用DTA研究了聚合物的热力学性质,其分解温度为501.1℃.  相似文献   

10.
合成了4种硫代碳酰腙类化合物双水杨醛硫代碳酰腙(BSTZ)、双对羟基苯甲醛硫代碳酰腙(BHBTZ)、双香兰素硫代碳酰腙(BMHBTZ)和双邻香兰素硫代碳酰腙(BMSTZ),其中苯环醛基对位具有羟基的BHBTZ和BMHBTZ能与超氧阴离子自由基(O-·2)、H2O2发生显色反应,而且BMHBTZ与O-·2的反应灵敏度为最高,由此建立了流动注射-光度法测定超氧阴离子自由基(O-·2)的方法.此方法的线性范围为4.5×10-7~1.5×10-6mol/L,线性方程为A698=1.8×104c(O-·2)+0.0045,相关系数r=0.9984,检出限为1.0×10-7mol/L.相对标准偏差为5.23%.大多数生物样品中共存物质无干扰  相似文献   

11.
Thermolysis of CoRu(CO)7(mu-PPh2) (1) in refluxing 1,2-dichloroethane in the presence of the diphosphine ligands 2,3-bis(diphenylphosphino)maleic anhydride (bma) and 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) furnishes the new mixed-metal complexes CoRu(CO)4(mu-P-P)(mu-PPh2) [where P-P = bma (3a), bpcd (3b)] along with trace amounts of the known complex CoRu(CO)6(PPh3)(mu-PPh2) (4). The requisite pentacarbonyl intermediates CoRu(CO)5(mu-P-P)(mu-PPh2) [where P-P = bma (2a), bpcd (2b)] have been prepared by separate routes (mild thermolysis and Me3NO activation) and studied for their conversion to CoRu(CO)4(mu-P-P)(mu-PPh2). The penta- and tetracarbonyl complexes have been isolated and fully characterized in solution by IR and NMR spectroscopy. The kinetics for the conversion of 2a-->3a and of 2b-->3b were measured by IR spectroscopy in chlorobenzene solvent. On the basis of the first-order rate constants, CO inhibition, and the activation parameters (2a-->3a, delta H++ = 29.2 +/- 1.4 kcal mol-1 and delta S++ = 8.2 +/- 3.8 eu; 2b-->3b, delta H++ = 27.7 +/- 0.6 kcal mol-1 and delta S++ = 1.4 +/- 1.6 eu), a mechanism involving dissociative CO loss as the rate-limiting step is proposed. The solid-state structure of CoRu(CO)4(mu-bma)(mu-PPh2) (3a), as determined by X-ray crystallography, reveals that the two PPh2 groups are bound to the ruthenium center while the maleic anhydride pi bond is coordinated to the cobalt atom.  相似文献   

12.
New synthesis procedures are described to tetranuclear manganese carboxylate complexes containing the [Mn(4)O(2)](8+) or [Mn(4)O(3)X](6+) (X(-) = MeCO(2)(-), F(-), Cl(-), Br(-), NO(3)(-)) core. These involve acidolysis reactions of [Mn(4)O(3)(O(2)CMe)(4)(dbm)(3)] (1; dbm is the anion of dibenzoylmethane) or [Mn(4)O(2)(O(2)CEt)(6)(dbm)(2)] (8) with HX (X(-) = F(-), Cl(-), Br(-), NO(3)(-)); high-yield routes to 1 and 8 are also described. The X(-) = NO(3)(-) complexes [Mn(4)O(3)(NO(3))(O(2)CR)(3)(R'(2)dbm)(3)] (R = Me, R' = H (6); R = Me, R' = Et (7); R = Et, R' = H (12)) represent the first synthesis of the [Mn(4)O(3)(NO(3))](6+) core, which contains an unusual eta(1):mu(3)-NO(3)(-) group. Treatment of known [Mn(4)O(2)(O(2)CEt)(7)(bpy)(2)](ClO(4)) with HNO(3) gives [Mn(4)O(2)(NO(3))(O(2)CEt)(6)(bpy)(2)](ClO(4)) (15) containing a eta(1):eta(1):mu-NO(3)(-) group bridging the two body Mn(III) ions of the [Mn(4)O(2)](8+) butterfly core. Complex 7 x 4CH(2)Cl(2) crystallizes in space group P2(1)2(1)2(1) with (at -168 degrees C) a = 21.110(3) A, b = 22.183(3) A, c = 15.958(2) A, Z = 4, and V = 7472.4(3) A(3). Complex 15 x (3)/(2)CH(2)Cl(2) crystallizes in space group P2(1)/c with (at -165 degrees C) a = 26.025(4) A, b = 13.488(2) A, c = 32.102(6) A, beta = 97.27(1) degrees, Z = 8, and V = 11178(5) A(3). Complex 7 contains a [Mn(4)(mu(3)-O)(3)(mu(3)-NO(3))](6+) core (3Mn(III), Mn(IV)) as seen for previous [Mn(4)O(3)X](6+) complexes. Complex 15 contains a butterfly [Mn(4)(mu(3)-O)(2)](8+) core. (1)H NMR spectra have been recorded for all complexes reported in this work and the various resonances assigned. All complexes retain their structural integrity on dissolution in chloroform and dichloromethane. Magnetic susceptibility (chi(M)) data were collected on 12 in the 5-300 K range in a 10.0 kG (1 T) field. Fitting of the data to the theoretical chi(M) vs T expression appropriate for a [Mn(4)O(3)X](6+) complex of C(3)(v)() symmetry gave J(34) = -23.9 cm(-)(1), J(33) = 4.9 cm(-)(1), and g = 1.98, where J(34) and J(33) refer to the Mn(III)Mn(IV) and Mn(III)Mn(III) pairwise exchange interactions, respectively. The ground state of the molecule is S = 9/2, as found previously for other [Mn(4)O(3)X](6+) complexes. This was confirmed by magnetization data collected at various fields and temperatures. Fitting of the data gave S = 9/2, D = -0.45 cm(-1), and g = 1.96, where D is the axial zero-field splitting parameter.  相似文献   

13.
14.
The syntheses of the stannatrane derivatives of the type N(CH(2)CMe(2)O)(3)SnX (1, X = Ot-Bu; 2, X = Oi-Pr; 3, X = 2,6-Me(2)C(6)H(3)O; 4, X = p-t-BuC(6)H(4)O; 5, X = p-NO(2)C(6)H(4)O; 6, X = p-FC(6)H(4)O; 7, X = p-PPh(2)C(6)H(4)O; 8, X = p-MeC(6)H(4)S; 9, X = o-NH(2)C(6)H(4)O; 10, X = OCPh(2)CH(2)NMe(2); 11, X = Ph(2)P(S)S; 12, X = p-t-BuC(6)H(4)C(O)O; 13, X = Cl; 14, X = Br; 15, X = I; 16, X = p-N(CH(2)CMe(2)O)(3)SnOSiMe(2)C(6)H(4)SiMe(2)O) are reported. The compounds are characterized by X-ray diffraction analyses (3-8, 11-16), multinuclear NMR spectroscopy, (13)C CP MAS (14) and (119)Sn CP MAS NMR (13, 14) spectroscopy, mass spectrometry and osmometric molecular weight determination (13). Electrochemical measurements show that anodic oxidation of the stannatranes 4 and 8 occurs via electrochemically reversible electron transfer resulting in the corresponding cation radicals. The latter were detected by cyclic voltammetry (CV) and real-time electron paramagnetic resonance spectroscopy (EPR). DFT calculations were performed to compare the stannatranes 4, 8, and 13 with the corresponding cation radicals 4(+?), 8(+?), and 13(+?), respectively.  相似文献   

15.
The geometric structure of trifluoroacetic anhydride, CF3C(O)OC(O)CF3, has been studied by gas electron diffraction (GED) and quantum chemical calculations (MP2 and B3LYP with 6-31G* basis sets). The GED analysis results in a single conformer with synperiplanar orientation of the two CO bonds. This analysis, however, cannot discriminate between a planar equilibrium structure (C2v symmetry) with large amplitude torsional motions around the OC bonds and a nonplanar equilibrium structure (C2 symmetry) with a low barrier at the planar arrangement. An effective dihedral angle φ(COCO=18(4)° is obtained. Both quantum chemical methods predict a nonplanar equilibrium structure of C2 symmetry and φ(COCO)=16.5° and 13.9°, respectively.  相似文献   

16.
The reaction of (R(2)PCH(2)SiMe(2))(2)NM (PNP(R)M; R = Cy; M = Li, Na, MgHal, Ag) with L(2)ReOX(3) [L(2) = (Ph(3)P)(2) or (Ph(3)PO)(Me(2)S); X = Cl, Br] gives (PNP(Cy))ReOX(2) as two isomers, mer,trans and mer,cis. These compounds undergo a double Si migration from N to O at 90 degrees C to form (POP(Cy))ReNX(2) as a mixture of mer,trans and fac,cis isomers. Additional thermolysis effects migration of CH(3) from Si to Re, along with compensating migration of halide from Re to Si. DFT calculations on various structural isomers support the greater thermodynamic stability of the POP/ReN isomer vs PNP/ReO and highlight the influence of the template effect on the reactivities of these species.  相似文献   

17.
以Al2O3为载体,采用等体积浸渍法制备了一系列Ni-Cu/Al2O3催化剂,用于顺酐液相加氢反应,并结合低温N2物理吸-脱附、H2程序升温还原、H2程序升温脱附、X射线衍射、CO程序升温表面反应等表征结果,详细考察了催化剂中Cu含量对其催化性能的影响.结果表明,Cu的引入提高了活性组分Ni的分散度,促进了催化剂上C=C的加氢活性;同时,由于Ni-Cu双金属间的相互作用,明显抑制了催化剂表面C=O的加氢.当Cu含量为7%时,催化剂上顺酐加氢定向合成丁二酸酐的活性最高.在210oC,H2压力5.0MPa的条件下反应40min时,顺酐转化率与丁二酸酐选择性均达100%.  相似文献   

18.
Abstract

Reaction of trifluoroacetic anhydride with chloroanhydrides of phosphorus acids R2P(O)CI results in formation of mixed anhydrides R2P(O) OCOCF3 and trifluoroacetic acid halides CF3COX (X=Cl, Br, I) in quantitative yield.  相似文献   

19.
A concise synthesis of (S)-3-hydroxytetrahydropyran from natural l-glutamic acid has been developed. The intramolecular etherification starting from 1,5-diol was promoted by trifluoromethanesulfonic anhydride. The clinnamates of the alcohols were prepared for accurately determining the optical purity by HPLC method.  相似文献   

20.
以正硅酸乙酯和硝酸铝分别为硅源和铝源,硝酸镍为活性组分前驱物,采用溶胶-凝胶法制备了NiO-SiO2,NiO-Al2O3和NiO-Al2O3-SiO2催化剂。顺酐液相选择加氢活性和选择性评价结果表明:顺酐在三种催化剂上转化率都在99%以上,而产物的选择性有较大的差别,其中NiO-SiO2催化剂上γ-丁内酯的选择性达80.1%,NiO-Al2O3催化剂上丁二酸酐选择性达99%以上,NiOAl2O3SiO2催化剂上两种产物都有。XRD,TPR等体相结构和表面结构的表征说明,三种催化剂的相组成、NiO的分散性及与载体的相互作用存在明显差别,这些差别可能是造成不同选择加氢性能的原因。  相似文献   

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