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IntroductionThe design and the synthesis of new chiral ox-azoline[1,2 ] and C2 symmetric bis( oxazoline) ligandsand the application of their metal complexes inasymmetric catalytic reactions have inspired manyscientists to great exertions in recent years[3— 8] .Our interest has been focussed on the studies ofenantioselective transition metal catalysis ofhetero-cyclic ligands[9— 11] . In the synthesis of our new de-signed ligands,what is crucial is to select a rigidcyclic backbone. Bis( oxazo…  相似文献   

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Two title compounds, 4,4'-diformyl-diphenoxyethane (compound 1, C16H14O4)and 4,4',4'-triformyl-triphenoxytriethylamine (compound 2, C27H27NO6), were synthesized by condensation of 4-hydroxybenzaldehyde with 1,2-dichloroethane and tris2-chloroethylamine, respectively in dimethyl formamide in the presence of anhydrous potassium carbonate. The crystal data are: monoclinic, P21/c, a = 7.571(2), b = 12.608(3), c = 7.357(2) ', = 105.823(6)o, V = 675.7(2)'3, Mr = 270.3, Z = 2, Dc = 1.328 g/cm3, F(000) = 284, (MoK = 0.096 mm-1, R = 0.0537 and wR = 0.2189 for compound 1; and monoclinic, P21/n, a = 11.7162(6), b = 9.0042(6), c = 22.908(2) ', = 99.505(1)°, V = 2383.5(3) '3, Mr = 461.50, Z = 4, Dc = 1.286 g/cm3, F(000)= 976, (MoK = 0.091 mm-1, R = 0.0464 and wR = 0.1462 for compound 2. The molecule of compound 1 dialdehyde is located at the crystallographic inversion center nearby the midpoint of C8-C8A single bond. The three chains in the molecule of compound 2 trialdehyde are of non-crystallographic pseudo-C3 symmetry, and each of them is quite planar.  相似文献   

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用萃取法合成了15种1,2-双(1'-苯基-3'-甲基-5'-氧代吡唑-4'-基)-1,2苯二酮(BPMOPP,简作H2L)稀土配合物。元素分析确定其化学组成为RE2L3·nH2O。通过电子光谱、红外光谱、核磁共振谱、热谱、摩尔电导等进行了表征,并讨论了配合物的性质。  相似文献   

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于鹏  景晓燕 《分析化学》1999,27(11):1337-1340
用^1H NMR和^13C NMR谱研究了新型电化学发光探针六氟磷酸二(4,4’;-二甲基-2,2‘-联吡啶).(4.4’-二羧酸-2,2‘-联吡啶)合钌的立体结构,通过^1H ^1H COSY,^13C-^1H HETCOR谱对其氢谱和碳谱中的各谱峰进行了归属,并给出了氢谱和碳谱峰的化学位移值。  相似文献   

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The present diversity in the definitions and relations of ‘verification’ and ‘validation’ is impractical for such transdisciplinary concepts. General dictionaries, international special language vocabularies and minor lists show that the respective recent formulations by the International Organization for Standardization (ISO) and the Joint Committee for Guides in Metrology (JCGM) are the most quoted. The characteristics of these concepts are elucidated terminologically, and separate concept systems are made for ISO and JCGM to arrive at a preference for a generic rather than an associative relation.  相似文献   

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合成了硝酸铒与四功能团含磷萃取剂6,6’-二(二苯基氧化膦甲基)-1,1’氮氧化-2,2’-联吡啶的配合物。用四圆衍射仪测定了配合物的晶体结构。金属离子周转的配位水分子已全部被取代。  相似文献   

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以新试剂2-(8’-羟基喹啉-5’-磺酸-7’-偶氮)-变色酸(简称8Q5SAC)作为显色剂,在硼砂-氢氧化钠缓冲体系中,用二阶导数吸光光度法测定微量镁,镁在0~15μg/25ml中符合比耳定律,可不经分离直接测定水样中镁,结果满意。  相似文献   

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