• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >Structural and Dynamic Studies on Amido-Bridged Rhodium and Iridium Complexes
【24h】

Structural and Dynamic Studies on Amido-Bridged Rhodium and Iridium Complexes

机译：酰胺桥铑和铱配合物的结构和动力学研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Treatment of [{M(mu-Cl)(diolefin)}_2] with the lithium salts of primary and secondary amines (LiNRR') in diethyl ether affords the complexes [{M(mu-NRR')(diolefin)}_2] (M = Rh, Ir; diolefin = 1,5-cyclooctadiene (cod), tetrafluorobenzobarrelene (tfb); R' = H, R = tBu, Ph, 4-MeC_6H_4; R = R' = Ph, 4-MeC_6H_4). Mixed-bridged chloro/amido complexes are intermediates in these syntheses, two of which, [{Rh(cod)}_2(mu-NHR)(mu-Cl)] (R = tBu, 4-MeC_6H_4), have been isolated. Replacement of the diolefin ligands by carbon monoxide or tert-butyl isocyanide inselected compounds takes place with retention of the binuclear structure to give the corresponding complexes [{M(mu-4-HNC_6H_~(4-)Me) (CO)_2}_2], [{Ru(mu-4-HNC_6H_4Me)-(CNtBu)_2}_2](12), AND [{Rh(mu-NPh_2)-(CNtBu)_2}_2] (13). Single-crystal X-ray diffraction analyses of the complexes [{Rh(mu-NRR')(COD)}_2] (R' = H, R = 4-MeC_6H_4 (3); R = R' = 4-MeC_6H_4 (5)), 12, and 13 have shown that the conformation of the "RhN_2Rh" four-membered metallacycle is planar in 5 and folded in 3, 12, and 13. The complexes with primary amides, 3 and 12, were found to exist as the syn, endo stereoisomers. The fluxionality of the complexes with secondary amides is due to rotation of the aromatic substituents about the N-C~(ipso) bond and, in the case of 13, to the inversion of the "RhN_2Rh" metallacycle as well. The complexes [{M(mu-NHR)(cod)}_2] (R = Ph, 4-MeC_~(6~-) H_4) were found to exist as isomeric mixtures in solution, the syn/anti ratio being 2:3 for the rhodium derivatives and 1:1 for their iridium counterparts. Again, the motion detected was due to rotation of the aromatic substituents, and could be frozen only in the case of the syn isomers. The complex [{Rh(mu-NHtBu)(cod)}_2] with aliphatic amido ligands was found to be the anti folded isomer and proved to be nonfluxional. The most common conformation of the "RhN_2Rh" metallacycle in these compounds is folded, and the preferred configuration varies from syn for the less encumbered compound to anti on increasing the bulkiness of the bridging and ancillary ligands.
机译：用伯胺和仲胺的锂盐（LiNRR'）在乙醚中处理[{M（mu-Cl）（di烯烃）} _ 2]，得到配合物[{M（mu-NRR'）（di烯烃）} _ 2] （M ＝ Rh，Ir;二烯烃＝ 1，5-环辛二烯（cod），四氟苯并戊烯（tfb）; R′＝ H，R ＝ tBu，Ph，4-MeC_6H_4; R ＝ R′＝ Ph，4-MeC_6H_4）。混合桥联的氯/酰胺基络合物是这些合成的中间体，已分离出其中的两种[{Rh（cod）} _ 2（mu-NHR）（mu-Cl）]（R = tBu，4-MeC_6H_4）。用一氧化碳或叔丁基异氰化物替换选定的二烯烃配体，同时保留双核结构，得到相应的络合物[{M（mu-4-HNC_6H_〜（4-）Me）（CO）_2} _2 ]，[{Ru（mu-4-HNC_6H_4Me）-（CNtBu）_2} _2]（12）和[{Rh（mu-NPh_2）-（CNtBu）_2} _2]（13）。配合物[{Rh（mu-NRR'）（COD）} _ 2]的单晶X射线衍射分析（R'= H，R = 4-MeC_6H_4（3）; R = R'= 4-MeC_6H_4（ 5）），12和13表明“ RhN_2Rh”四元金属环的构象在5中为平面，并在3、12和13中折叠。发现存在与伯酰胺的配合物3和12。作为顺式，内立体异构体。具有仲酰胺的络合物的通量是由于芳族取代基绕N-C-（ipso）键旋转，并且在13的情况下，还由于“ RhN_2Rh”金属环的反转。发现络合物[{M（mu-NHR）（cod）} _ 2]（R = Ph，4-MeC_〜（6〜-）H_4）以异构体混合物形式存在于溶液中，顺/反比为2：铑衍生物为3，铱化合物为1：1。同样，检测到的运动归因于芳族取代基的旋转，并且仅在顺式异构体的情况下可以冻结。发现具有脂族酰胺基配体的配合物[{Rh（mu-NHtBu）（cod）} _ 2]是抗折叠的异构体，被证明是非氟代的。这些化合物中最常见的“ RhN_2Rh”金属环的构型被折叠，并且优选的构型从较少阻碍的化合物的顺式变化到桥接和辅助配体的体积增加。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号