Schibli Roger, Alberto Roger, Abram Ulrich, Abram Sonja, Egli André, Schubiger P. August, Kaden Thomas A.
Center for Radiological Research, University of Missouri, Columbia, Missouri 65211, Division of Radiopharmacy, Paul Scherrer Institute, CH-5232 Villigen, Switzerland, Forschungszentrum Rossendorf, Institute of Radiochemistry, c/o Dresden University of Technology, D-01062 Dresden, Germany, and Institute of Inorganic Chemistry, Spitalstrasse 51, CH-4056 Basel, Switzerland.
Inorg Chem. 1998 Jul 13;37(14):3509-3516. doi: 10.1021/ic980112f.
Starting originally from the organometallic precursor NEt(4)[TcBr(3)(CO)(3)] (1b), substitution reactions were performed with the macrocyclic thioethers 1,4,7-trithiacyclononane (9-ane-S(3)), 1,4,7,10,13,16-hexathiacyclooctadecane (18-ane-S(6)), and 3,6,9,13,16,19-hexathiacycloicosanol (20-ane-S(6)-OH). The corresponding complexes fac-[Tc(9-ane-S(3))(CO)(3)]Br (2), fac-[Tc(2)(tosylate)(2)(18-ane-S(6))(CO)(6)] (3), and fac-[Tc(2)(20-ane-S(6)-OH)(CO)(6)]tosylate (5) were isolated in good yields and characterized spectroscopically by IR, (1)H, (99)Tc NMR, and X-ray diffraction methods. In the case of 18-ane-S(6) and 20-ane-S(6)-OH the formation of the 1:2 as well as the 1:1 complex could be observed in the (99)Tc NMR experiment, depending on the ligand to metal ratio. Complex 2crystallizes in the monoclinic space group P2(1)/c, a = 14.79(2) Å, b = 11.691(2) Å, c = 16.94(2) Å, beta = 94.88(6) degrees, Z = 8. The tripodal ligand is coordinated through the sulfur atoms to the metal center, forming three favorable five-membered chelate rings. Complex 3 crystallizes in the monoclinic space group C2/c, a = 26.073(4) Å, b = 9.288(1) Å, c = 17.898(3) Å, beta = 99.84(1) degrees, Z = 4. The binuclear unit is formed by two fac-[Tc(tosylate)(CO)(3)] moieties which are trans, bidentate coordinated to the macrocyclic ligand. Compound 5 crystallizes in the monoclinic space group Pc, a = 25.737(4) Å, b = 14.009(1) Å, c = 26.479(3) Å, beta = 149.56(2) degrees, Z = 4. In the case of the dicationic compound 5, the two Tc(I) centers are tripodal, cis coordinated toward the thia crown ether. A detailed analysis of the ring conformation in the solid state structure explained to a certain extent the formation of only one isomer (trans in the case of 3 and cis in the case of 5, respectively) during the substitution reaction.
最初从有机金属前体NEt(4)[TcBr(3)(CO)(3)]（1b）开始，与大环硫醚1,4,7 - 三硫杂环壬烷（9 - ane - S(3)）、1,4,7,10,13,16 - 六硫杂环十八烷（18 - ane - S(6)）和3,6,9,13,16,19 - 六硫杂环二十醇（20 - ane - S(6)-OH）进行取代反应。相应的配合物面式 - [Tc(9 - ane - S(3))(CO)(3)]Br（2）、面式 - [Tc(2)(对甲苯磺酸根)(2)(18 - ane - S(6))(CO)(6)]（3）和面式 - [Tc(2)(20 - ane - S(6)-OH)(CO)(6)]对甲苯磺酸根（5）以良好的产率分离出来，并通过红外光谱、(1)H、(99)Tc核磁共振和X射线衍射方法进行了光谱表征。在18 - ane - S(6)和20 - ane - S(6)-OH的情况下，根据配体与金属的比例，在(99)Tc核磁共振实验中可以观察到1:2以及1:1配合物的形成。配合物2在单斜空间群P2(1)/c中结晶，a = 14.79(2) Å，b = 11.691(2) Å，c = 16.94(2) Å，β = 94.88(6)°，Z = 8。三脚架配体通过硫原子与金属中心配位，形成三个有利的五元螯合环。配合物3在单斜空间群C2/c中结晶，a = 26.073(4) Å，b = 9.288(1) Å，c = 17.898(3) Å，β = 99.84(1)°，Z = 4。双核单元由两个面式 - [Tc(对甲苯磺酸根)(CO)(3)]部分组成，它们是反式的，双齿配位到大环配体上。化合物5在单斜空间群Pc中结晶，a = 25.737(4) Å，b = 14.009(1) Å，c = 26.479(3) Å，β = 149.56(2)°，Z = 4。在二价阳离子化合物5的情况下，两个Tc(I)中心呈三脚架状，顺式配位到硫杂冠醚上。对固态结构中环构象的详细分析在一定程度上解释了取代反应过程中仅形成一种异构体（分别在3的情况下为反式，在5的情况下为顺式）的原因。
