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1.
多组份含金属盐透明树脂的合成   总被引:2,自引:0,他引:2  
本文将双烯聚醚砜大分子单体(BPS-MA)引入含金属(Pb、Ba等)盐单体的苯乙烯体系中进行聚合,发现单体配比与树脂透明性密切相关。对于Pb(MA)_2/St/MA/BPS-MA四元体系,欲获得透明树脂,BPS-MA用量大于20%时,摩尔比MA/[Pb(MA)_2]可由原来的5.5降至2.2左右,并且可获得n_D>1.60的透明材料。光学性能测试结果表明,Pb(MA)_2、BPS-MA量增加,n_D增大,阿贝数v_D略降低;MA量增加,n_D下降v_D略增加。适当的配比可望制备出性能优异的多组份含金属盐透明聚合物材料。  相似文献   

2.
<正> The compound [Et_4N]_2[Fe_2S_2(NO)_4] (M_r=556.36) crystallizes in the monoclinic,space group P 2_1/n with a=9. 688(3), b=10. 882(2), c=12. 625(2), β=97. 86(3)°, Z=2, V=1318. 4, D_c=1. 40g/cm~3, ;μ(MoK_a)=12. 8cm~(-1) and F(000)=588. The final R=0. 028 and R_w=0. 029 for 2041 reflections (I≥3σ(I)).The crystals of [Et_4N]_2[Fe_2S_2(NO)_4] consist of discrete cations [Et_4N]~+ and anions  相似文献   

3.
苯并15-冠-5与Na_2[M(SCN)_4](M=Pd,Pt)配合物的合成与结构   总被引:2,自引:0,他引:2  
合成了苯并15-冠-5与Na_2[M(SCN)_4] (M = Pd, Pt)生成的配合物:[Na(B15- C-5)]_2[Pd(SCN)_4] (1), {[Na(B15-C-5)][Na(B15-C-5)(H_2O)]}[Pt(SCN)_4] (2)。1为单斜晶系,空间群P2_1/n,a = 1.0164(6) nm,b = 1.3743(3) nm,c = 1.4987(7) nm,β = 95.248(6)°,V = 2.0847 nm~3,Z = 2,D_(calcd) = 1. 47 g/cm~3,F(000) = 944,R = 0.053,wR = 0.072。2为三斜晶系,空间群P(1- bar),a = 1.1484(2) nm,b = 1.4210(3) nm,c = 1.5026(3) nm,α = 62.500 (3)°,β = 72.393(3)°,γ = 73.106(4)°,V = 2.0398(7) nm~3,Z = 2, D_(calcd) = 1.674 g/cm~3,F(000) = 1028,R_1 = 0.0327,wR_2 = 0.0885。1 由两个[Na(B15-C-5)]~+配阳离子和一个[Pd(SCN)_4]~(2-)配阴离子组成,两者通 过Na-N键形成中性配合物,[Na(B15-C-5)]~+A相对钯原子呈反式排列。2由[Na (B15-C-5)]~+和[Na(B15-C-5)(H_2O)]~+配阳离子和一个[Pt(SCN)_4]~(2-)配阴离 子组成,它们也通过Na-N键形成中性配合物,配阳离子相对铂原子呈顺式排列。2 的两个分子通过氢键形成二聚结构。  相似文献   

4.
在乙腈溶液中(Et_4N)_2[Fe_4(SR)_(10)]与(Et_4N)_2[MoS_4]反应半小时生成对氧极为敏感的系列黑色晶状化合物(Et_4N)_4[Mo_2Fe_7S_8(SR)_(12)(R=C_6H_5,1;R=C_6H_4CH_3-m,2;R=C_6H_4CH_3-o,3;R=C_6H_4CH_3-p,4).2·2THF晶体的分子量为2982.8,属单斜晶系;空间群为P2_1/n;α=18.022(2),b=18.375(2),c=22.254(3)A;β=71.04(1)°;V=6969(2)A~3;D_(?)=1.424g·cm~(-3);Z=2;F(000)=3108.晶体结构用直接法解出,修正至R=0.064.2.2THF中Mo…Mo′距离为7.234A.  相似文献   

5.
A new terbium(Ⅲ) complex Tb_2(C_(15)H_(11)O_3)_6(phen)_2 has been synthesized with 2-(4-methylbenzoyl)benzoic acid and 1,10-phenanthroline as ligands.Crystal data for the complex are as follows:monoclinic,space group P2_1/n,a=15.0786(6),b=13.5762(5),c=22.9683(9) A,β=104.130(4)°,V=4559.6(3) A~3,D_c=1.540_g/cm~3,Z=2,μ(MoKα)=1.615 mm~(-1),F(000)=2136,the final R=0.0528 and wR=0.0740.The Tb(Ⅲ) ion is coordinated by eight atoms to give a distorted square antiprism coordination geometry.The complex shows four fluorescence emission bands arising from the transitions of Tb~(3+5)D_4→~7F_6(490 nm),~5D_4→~7F_5(546 nm),~5D_4→~7F_4(588 nm) and ~5D_4→~7F_3(622 nm).The complex is an antiferromagnet in the range of 300~2 K.Also reported in the paper is the thermal stability property of the title complex.  相似文献   

6.
含铅透明树脂聚合分相及其光学特性研究   总被引:4,自引:1,他引:4  
<正> 在分子链中引入金属离子可以提高聚合物材料的玻璃化转变温度和折光指数,研制防辐射材料及有机发光材料,但含有重金属离子的树脂在聚合时体系易产生分相出现半透明或不透明,影响材料的透光性。本文研究了甲基丙烯酸铅[Pb(MA)_2]与苯乙烯(St)、甲基丙烯酸(MA)及甲基丙烯酸甲酯(MMA)共聚过程分相及  相似文献   

7.
The oxidation-reduction reaction of the molybdenum cluster compound Mo_3(μ_3-S)(μ-S)_2-[μ-SOP(OEt)_2] [S_2P(OEt)_2]_3(O)_2 with CuCl_2·2H_2O has been investigated and the chemical components of its product, Cu_8Cl_2[S_2P(OEt)_2]_6, were confirmed. The crystal belongs to the triclinic system and the space group is P with the following unit cell parameters: a=11.578 (5), b=12.663 (3), c=14.317 (4); α=55.54 (2)°, β=57.35 (3)°, γ=72.23 (3)°; Z=1; D_(calc)=1.926 g·cm~(-3). Final discrepancy factor of R is 0.075 for 3573 unique reflections with I≥3σ(I). The results of investigation show that the crystal structure consists of molecular chains with Cu_8Cl_2[S_2P(OEt)_2]_6 as structural unit, in which eight Cu atoms form a cube-shaped cage. The coordination sphere of each Cu atom is a tetrahedron configuration. The distances between Cu atoms are 3.018-3.437, which indicates that there are no metal-metal bonds between Cu atoms. It is worthwhile to study further the phenomenon how Cu(+2) captures the  相似文献   

8.
合成了苯并15-冠-5、二苯并18-冠-6与Na_2[Pt(SCN)_6]的配合物:[Na(B15- C-5)]_2[Pt(SCN)_6] (1),[Na(DB18-C-6)]_2[Pt(SCN)_6] (2),并通过元素分析 、红外光谱、单晶X射线衍射进行了表征。1为单斜晶系,空间群P2_1/c,a = 1. 0974(5) nm,b = 1.5187(7) nm,c = 1.3632(6) nm,β = 96.407(7)°,V = 2. 2568(18) nm~3,Z = 2,D_(calcd) = 1.746 g/cm~3,F(000) = 1184,R_1 = 0. 0357,wR_2 = 0.0868。 2为三斜晶系,空间群 P1-bar,a = 1.2500(3) nm,b = 1.2825(3) nm,c = 1.9342(4) nm,α = 106.82(3)°,β = 102.51(3)°,γ = 103.04(3)°,V = 2.7562 nm~3,Z = 2,D_(calcd) = 1.579 g/cm~3,F(000) = 1316,R_1 = 0.0364,wR_2 = 0.0771。配合物分别由两个[Na(B15-C-5)]~+, [Na(DB18-C-6)]~+配阳离子和一个[Pt(SCN)_6]~(2-)配阴离子组成。配阳离子和配 阴离子通过Na-N键形成二维网状结构。  相似文献   

9.
本工作研究了CL—7301萃淋树脂从含铼钼的H_2SO_4-(NH_4)_2SO_4水溶液中分离铼钼的性能。铼和钼的吸附率都随溶液酸度增加而降低,但铼的吸附率远比钼的大。两者的分离系数在1~6N酸度范围内4N时有最大值,β_(Mo)~(Re)=120。铼的饱和吸附容量随铼浓度的增加而增大。柱吸附实验表明,铼的吸附容量达28毫克·克~(-1)树脂。用氨水淋洗铼几乎全部被洗脱,回收率接近100%,而钼的吸附量低于0.17毫克·克~(-1)树脂。溶液的铼含量可由0.3克·升~(-1)浓集到10克·升~(-1)以上,钼含量由5.0克·升~(-1)降至0.05克·升~(-1)以下,使二者达到有效的分离。  相似文献   

10.
本文报道三重桥氧三核铬脂肪酸配合物[Cr_3(μ_3-O)(μ-OOCH)_6(H_2O)_2OOCH]和[Cr_3(μ_3-O)(μ-OOCR)_6(H_2O)_3]~+(R=CH_3,C_2H_5和C_3H_7)的快原子轰击(FAB)质谱。当桥配体为甲酸基时获得完整的配位阳离子峰(其单晶结构见文献),由于质子亲电进攻端配体甲酸基的氧,从而形成了质子化的[Cr_3(μ_3-O)(μ-OOCH)_6(H_2O)_2HCOOH]~+离子。后者可以失去CO生成[Cr_3(μ_3-O)(μ-OOCH)_6(H_2O)_3]~+,进一步的断裂和乙酸配位时的情况相同,可连续脱三个配位水,分别生成[Cr_3O(OOCR)_6(H_2O)_2]~+、[Cr_3O(OOCR)_6(H_2O)]~+和[Cr_3O(OOCR)_6]~+离子;并可进一步脱桥配基或RCO,分别生成[Cr_3O(OOCR)_5]~+、[Cr_3O(OOCR)_4]~+、[Cr_3O(OOCR)_3]~+、[Cr_3O(OOCR)_5O]~+、[Cr_3O(OOCR)_4O]~+、[Cr_3O(OOCR)_3O]~+和[Cr_3O(OOCR)_2O]~+等碎片离子。当桥配体为丙酸和丁酸时,主要观察到[Cr_3O(OOCR)_6]~+离子及其进一步断裂所形成的碎片离子,断裂过程和乙酸配位时基本相似;另外这类配合物都还形成一系列由FAB底物参与的加成离子。基于以上分析,我们提出了这类配合物可能的断裂过程,并认为随着脂肪酸碳链的增长,整个配位阳离子的稳定性下降。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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