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1.
N-甲基吗啉对5-(l-薄荷烷氧基)-2(5H)-呋喃酮的光催化不对称共轭加生成了4-(S)-[2-(N-甲基)吗啉基]-5-(R)-(l-薄荷烷氧基)-丁内酯,在四氢呋喃(THF)对比实验、参比物^13CNMR对照及不同溶剂^13CNMR测定的基础上,该新化合物的结构用高分辨率的子核磁共振谱、碳核磁共振谱、质谱、红外光谱及元素分析、旋光度等数据进行了确证。  相似文献   

2.
<正> Mr=996.91, triclinic, P1, a=8.773(2), b=9.712(3), c=13.652(1) A; α=69.24(0), β=70.43(3), γ=66.87(l)°; Z=l, Dx=1.699 g/cm 3. Final R=0.053 for 3186 reflections with I≥3a(I). There is an interesting trans influence of μ-s bridge in this binuclear cluster. Mo-Mo distance is 2.752(1) A.  相似文献   

3.
本文用CNDO/2方法研究了(dmpe)_2H_tCrBH_4(Ⅰ)、(dmpe)_2H_tCrAlH_4(Ⅱ)和[(dmpe)_2H_tCrAlH_4]_2(Ⅲ)(dmpe=(CH_3)_2PCH_2CH_2P(CH_3)_2,在计算时,我们用二个PH_3代替一个(dmpe)的电子结构。结果表明:(1)在(Ⅱ)的6b_1(HOMO),7a_1占据轨道中,Cr3d轨道与2H_b1S轨道(H_b为桥氢原子)对称性不匹配,相互排斥,而在(Ⅰ)中这种排斥有所减弱;Cr(u-H_b)_2Al骨架较Cr(u-H_b)_2B能量高而不稳定。(2)在(Ⅲ)的电子结构中Cr3d与2H_b1S之间排斥大为减弱,Cr(u-H_b)_2Al稳定性提高;新形成的AL(u-H)_2AL能量较低;在较高占据轨道中H_t和H_b成份多,活泼性强,这可能是H_t和H_b易交换的主要原因。三个化合物在电子结构上的差异较合理解释了实验现象。  相似文献   

4.
分光光度法测定钯的新显色剂 2-四唑偶氮-5-二乙氨基酚   总被引:2,自引:0,他引:2  
研究了新显色剂2_四唑偶氮_5_二乙氨基酚 (TTZAPN)分光光度法测定Pd2 的条件。在 pH5.0的HAc -NaAc介质中 ,该试剂与Pd2 形成稳定的摩尔比为2∶1的紫红色络合物。其最大吸收波长在530nm处 ,表观摩尔吸光系数为4.51×104L·mol -1·cm -1 ,Pd2 质量浓度在0~1.0mg/L范围内遵守比尔定律。所拟方法直接测定钯 -碳催化剂和分子筛中微量钯 ,结果令人满意。  相似文献   

5.
配合物Li(THF)_2(μ-Cl)_2YCl_2(THF)_2,M=526.10,结构已由X射线衍射法测定,空间群C_2/c,a=21.333(5),b=10.371(10),c=22.559(4)(?),β=90.87(1)°,V=4990.4(?)~3,Z=8,μ(Cu K_a)=75.378cm~(-1),F(000)=2160,R=0.073。  相似文献   

6.
<正> Introduction. The complexes of Mo(V) and oxalate are found to exist in several various configurations. As an anologous compound for the activecenter of Mo enzymes they have attracted broad attention. It was found by Sobczak and Ziolkowski in 1976 that these types of complexes had a higher catalytic selectivity in the epoxidation of olefine by hydroperoxides  相似文献   

7.
<正> M=1140.85, monoclinic, P21/c. a=12.748(2), b=14.320(2), c=23.118 (3)A,β=101.07(1)°, V=4141(2)A3, Z=4, Dc=1.830 g.cm-3. Final R=0.039 for 4160 reflections.The title compound is a rather irregular trinuclear molybdenum cluster having only two M-M bonds with two shorter Mo-Mo distances of 2.808(1), 2.839(1), and one longer Mo-Mo distance of 3.337(1)8. The existence of two Mo-Mo bonds is coincident with the electron counting for {Mo3} cluster core, and may be regarded as a result of the oxidation of a compound Mo3(μ3-S)(μ-S)2 (μ-L)[S2P(OEt)2]4(L') (L'=neutral ligands)1 characterized by us previously.  相似文献   

8.
通过水热合成的方法,以1,4-环己烷二羧酸、2,4-二氨基-6-甲基三嗪和CdCl_2·2.5H_2O为原料合成了一种单核的化合物{Cd(dmt)_2(Hchdc)_2(H_2O)_2}_n(dmt=2,4-diamino-6-methyl-triazine,H2chdc=1,4-cyclohexanedicarboxylic acid),并进行了IR和X射线单晶衍射(常温)的分析.结果表明,该化合物属于P2/c空间群,单斜晶系,晶胞参数:a=1.330 26(11)nm,b=0.541 47(4)nm,c=2.415 54(16)nm,β=115.751(3)°,V=1.567 1(2)nm~3,Z=2,Dc=1.570g/cm~3,F(000)=764,R1=0.035 2,wR2=0.092 7.该化合物中,中心金属离子Cd(II)与氧相连形成六配位构型,并通过4种不同的氢键作用最终形成了三维的堆积结构.  相似文献   

9.
<正> [(C2H5)4N]2[Mo2o2S2(S2)2], Mr = 676. 74, monoclinic, P21/c, a = 13.510(2), b = 14.373(2), c=14. 777(3)(?), β = 97.53(2)°, V = 2844.7(9) (?)3, Z = 4, Dc= 1. 58g/cm3, μ(MoKα) = 13.0cm-1, F(000) = 1384, R =0. 033 for 1803 observed reflections. The structure contains discrete [Mo2O2S2(S2)2]2- anions and Et4N+ cations. The two oxygen atoms bonded to the Mo atoms are in cis-form with respect to the Mo2S2 bridging unit, with an average Mo- O distance of 1. 678 (?), The Mo…Mo distance is 2. 832(1)(?).  相似文献   

10.
Wayda最近报道,无水氯化稀土LnCl_3和叔丁基环戊二烯钠(t-BuCp)Na进行交换反应时,由于歧化反应得不到单取代或双取代的轻稀土氯化物衍生物,只能得到中稀土和重稀土氯化物衍生物,并且没有测得这些配合物的晶体结构。我们采用提高反应温度和延长反应时间,使交换反应进行完全,有效地避免了歧化反应的发生,成功地分离到了单取代或双取代的叔丁基环戊二烯基轻稀土氯化物。并测得(t-BuCp)_2LnCl·nTHF(Ln=Pr,n=2;Ln=Yb,n=1)  相似文献   

11.
魏丹毅  郑岳青  林建利 《化学学报》2002,60(7):1248-1252
在甲醇与水的混合溶剂中,经浓硝酸硝化的Ho_2O_3与1,10-邻菲啰啉反应形 成氢氧根桥联的双核钬配合物[Ho_2(phen)_4(H_2O)_4(OH)_2] (phen)_2(NO_3)_4 (phen = 1,10-邻菲啰啉)。单晶X射线衍射晶体结构测定表明晶体属三斜晶系, P1-bar (no. 2)空间群,晶胞参数a = 1.1241(1) nm, b = 1.1439(1) nm, c = 1. 4058 (1) nm, α = 93.989(7)°, β = 98.173(7)°, γ = 108.19(1)°, V = 1.6874(4) nm~3, Z = 1, D_c = 1.737 g/cm~3, F(000) = 880,7752个独立衍射 点中,5702个可观测点满足F_o~2 ≥ 2σ (F_o~2),R_1 = 0.0499, wR_2 = 0. 858。标题配合物由中心对称的双核[Ho_2(phen)_4(H_2O)_4-(OH)_2]~(4+)配阳离 子,邻菲啰啉phen分子及硝酸根NO_3~-阴离子组成。敏个稀土原子与2个邻菲啰啉 配体,2相水分子和2个氢氧根配位形成配位数为8的[HoN_4O_4]四方反棱柱。配位 多面体通过两氢氧根基团形成共棱的[Ho_2N_8O_6]双四方反棱柱[d(Ho-N) = 0. 2549~0.2565 nm, d(Ho-O_(H_2O) = 0.2356, 0.2366 nm, d(Ho-O_(OH)) = 0. 2223, 0.2240 nm]。通过氢键和芳环堆积作用,配阳离子和邻菲啰啉分子排列形成 平行于(10 1-bar)的两维层结构,NO_3~-阴离子位于层之间。标题配合物为顺磁 物质,在5 ~300K区间内遵循Curie-Weiss定律X_m (T + 4.43) = 14.72 cm~3·K ·mol~(-1)(X_m为每摩尔Ho~(3+)离子磁化率),其Ho~(3+)离子的室温有效磁矩为 10.76 B. M.,与Ho~(3+)自由离子的磁矩基本相同,表明稀土离子间不存在磁交换 作用。  相似文献   

12.
<正> M=1013.98, hexagonal, P63/m, a=b=15.492(2), c=8.530(4)A, γ=120°, V=1773A3, Z=2, Dc=1.899°g.cm-3. Final R=0.042 for 611 reflections.This is a Bl(bicapped) type trinuclear molybdenum cluster with two S capping atoms located on the 63 axis and exhibits full D3h symmetry. The Mo-Mo distances are 2.606(1)A, with a bond order of 11/3. It is paramagnetic.  相似文献   

13.
<正> The molecular and crystal structure of the complex (μ-HOCH2CH2-S)2 Fe2(CO)4(PPh3)2 synthesized by reaction of ethylene epoxide with (μ-Lis)2Fe2(CO)6, followed by EtOH alcoholysis and PPh3 substitution,was determined by X-ray diffraction technique. The crystals are triclinic,space group P 1,with a= 10. 902(2),b=12. 106 (2),c=16. 123(4) A ,V= 2079. 36A3,α=78. 13(1),β=89. 37(2),γ=87. 93(1)°, Z = 2,Dx=1. 44 g/cm3.μ(MoKa) = 9. 149cm-1, F(000) = 940. The final R and Rw equal to 0. 055 and 0. 068,respectively,for 3598 observed independent reflections. In this molecule two PPh3 ligands are trans to the Fe - Fe bond and axially coordinated to two iron atoms. In addition,two hydroxylethyl groups are attached to bridging sulfur atoms by e-type of bond and thus this molecule is an ee conformer.  相似文献   

14.
<正> (η5-C5H5)W2Fe2(μ3-S)2(CO)8,Mr = 897. 80,monoclinic,C2/c,a= 18. 019 (2),b = 8. 330(1),c= 16. 043(2) A ,β= 114. 30(1)°,v = 2194. 7(6)A3,z= 4, Dx = 2. 717g/cm3, A(MoKa) = 0. 71037 A , μ= 122. 01cm-1, F (000) = 1656, T = 295K,R=0.056,Rw = 0. 059 for 1250 observed reflections. The crystals of the title compound are isomorphous with the analog (η5-C5H5)2Mo2Fe2(μ3-S)2(CO)8.  相似文献   

15.
施继成  黄小荥 《结构化学》1995,14(4):293-296
SynthesisandCrystalStructureof(Et_4N)_2[Pd_2(mp)_2(mpH)_2]ShiJi-Cheng;HuangXiao-Ying;WenTing-Bin;DengYu-Heng;ChengChang-Neng;Li?..  相似文献   

16.
1 INTRODUCTION Polyoxomolybdates have been of great interest due to their unique structural varieties, associated multitude of properties and applications as catalysis, medicine and material[1, 2]. One of the most impor- tant aspects is the synthesis and investigation of the materials on polyoxomolybdates containing organo- metallic groups[3~5]. Such materials can provide molecular models for heterogeneous catalysis and display cooperative effects or bifunctional catalytic activity[6]. O…  相似文献   

17.
The polyoxoanion incorporated {Mn(CO)3+} complex, (n-Bu4N)2[Mo6O16(OCH3)2{HOCH2C(CH2O)3}2· {Mn(CO)3}2](1), has been synthesized by the reaction of (n-Bu4N)4[Mo8O26] with Mn(CO)5Br in methanol, in the presence of C(CH2OH)4. The complex 1 has been characterized by IR, UV-Vis, X-ray single crystal diffraction, and TG. Crystal data for the complex 1: C25H48MnMo3NO16 (1), Triclinic P1, a=0.9405(3) nm, b=1.3351(4) nm, c=1.5455(4) nm, α=103.206(5)o, β=102.165(5)o, γ=100.784(5)o, V=1.7896(9) nm3, Z=2, R1=0.0703, wR...  相似文献   

18.
本文合成了标题配合物,对其红外光谱进行了研究.测定了配合物的晶体结构,结果表明,晶体属三斜晶系,P1空间群,单胞参数:α=11.549(2)(?),b=14.122(3)(?),c=15.654(?),α=97.01(2)°,β=102.70(2)°,γ=105.43(2)°,V=2355.94(0.87)(?)~3,Z=2.晶体结构是采用Patterson法和差值Fourier合成解出.经全矩阵最小二乘法修正,最后偏差因子R=0.0337,R_w=0.0364.晶体中甘氨酸与Sm原子的结合方式有三种:第一种甘氨酸的羧基离子以螯合桥式与Sm原子配位;第二种甘氨酸以羧基桥式与同一单元的两个Sm原子配位;第三种甘氨酸以酸基桥式连结两个相邻单元中的相邻Sm原子而形成一维无限长链结构.此外,每个Sm原子还与两个水分子成键,其配位数为9.  相似文献   

19.
MgCl_2负载(dbm)_2Ti(OPh)_2催化乙烯聚合   总被引:4,自引:0,他引:4  
烯烃聚合的新型非茂催化剂由于合成相对简便并具有一些新特点,近年来开始受到人们的关注[1,2].IVB族金属的β二酮络合物与烷基铝或烷氧基铝形成的催化体系对烯烃聚合也显现出一定的聚合活性.在一定压力下,β二酮锆/MAO均相催化乙烯聚合时具有较高聚合活性[3].β二酮钛催化剂对于丙烯无规聚合和苯乙烯间规聚合均有较好结果[4~6].本文将报道用MgCl2负载的二苯氧基二(二苯甲酰甲烷)钛络合物((dbm)2Ti(OPh)2),以甲基铝氧烷(MAO)为助催化剂,常压催化乙烯聚合的结果.1 原料MgCl2为抚顺301厂产品.MAO(1.4mol/L甲…  相似文献   

20.
二(叔丁基环戊二烯基)钕甲基配合物催化丙烯腈聚合   总被引:7,自引:0,他引:7  
任劲松  沈琪 《应用化学》1995,12(3):105-106
二(叔丁基环戊二烯基)钕甲基配合物催化丙烯腈聚合任劲松,扈晶余,沈琪(中国科学院长春应用化学研究所稀土化学与物理开放实验室长春130022)(苏州大学化学系苏州)关键词丙烯腈,配位聚合,钕配合物丙烯腈聚合通常采用BF_3、TiCl_4、过氧化苯甲酰 ̄...  相似文献   

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