Chiral Sulfur Functional Groups as Definers of the Chirality at the Metal in Ir and Rh Half-Sandwich Complexes: A Combined CD/X-ray Study
作者:Marta G. Avello、María Frutos、María C. de la Torre、Alma Viso、Marina Velado、Roberto Fernández de la Pradilla、Miguel A. Sierra、Heinz Gornitzka、Catherine Hemmert
DOI:10.1002/chem.201702662
日期:2017.10.17
Mesoionic carbenes (MICs) derived from triazoliumsalts that contain chiral sulfoxide or sulfoximine functional groups were used to construct enantiopure chiral‐at‐metal IrIII and RhIII half‐sandwich complexes through the synthetic sequence of MIC complexation/C−H aromatic activation. The process was efficient and diastereoselective for the formation of enantiopure five‐membered metallacycles. The
通过含有MIC络合物/ CH-H芳族活化序列的合成序列,由三唑鎓盐衍生而来的中离子卡宾(MIC)用于手性亚金属Ir III和Rh III半夹心复合物,构成对映体纯的手性金属Ir III和Rh III半三明治复合物。该过程对于形成对映纯五元金属环来说是高效且非对映选择性的。手性硫基对映体的使用使我们能够制备在金属中心具有相反构型的配合物。阳离子的Ir的形成过程中,观察到在金属中心的结构的完全保留III复合物并且在炔烃插入铱III-C键,如圆二色性/ X射线研究所证实。这些结果表明了一种类似S N 1的邻近辅助机制。
Sulfur Groups Improve the Performance of Triazole- and Triazolium-Based Interaction Units in Anion Binding
作者:Mónica Álvarez-Pérez、Marina Velado、Diego García-Puentes、Elena Sáez、Cristina Vicent、Roberto Fernández de la Pradilla、Alma Viso、María C. de la Torre、Miguel A. Sierra
DOI:10.1021/acs.joc.7b00261
日期:2017.3.17
An NMR comparative study of 1,2,3-triazole and triazolium anion recognition units containing sulfoxide, sulfone, and sulfoximine groups at C4 unveils an enhancement in binding ability up to ≈1 kcal/mol in acetone-d6 correlated with a theoretical increase of H5 acidity. DFT calculations provide insight into binding modes in line with experimental data for these receptors.
NMR比较研究了C 4处含有亚砜,砜和亚砜亚胺基团的1,2,3-三唑和三唑鎓阴离子识别单元,揭示了在丙酮中的结合能力提高到≈1kcal / mol- d 6与理论值相关H 5酸度增加。DFT计算可根据这些受体的实验数据深入了解结合模式。