fac-[Re(CO)3(HNC(CH3)NHCH(CH3)2)(5,5'-Me2bipy)]BF4 | 1236848-44-4

• 英文名称: fac-[Re(CO)3(HNC(CH3)NHCH(CH3)2)(5,5'-Me2bipy)]BF4
• 英文别名: fac-[Re(CO)3(HNC(CH3)NHCH(CH3)2)(5,5'-dimethyl-2,2'-bipyridine)]BF4
• CAS: 1236848-44-4；1246224-25-8
• 化学式: BF₄*C₂₀H₂₄N₄O₃Re
• 分子量: 641.447
• InChiKey: WKXNWESEIAQEKP-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
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• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为产物：
  描述：

  [Re(CO)3(5,5′-Me2bipy)(CH3CN)]BF4 、 异丙胺 以 乙腈 为溶剂， 以63%的产率得到fac-[Re(CO)3(HNC(CH3)NHCH(CH3)2)(5,5'-Me2bipy)]BF4
  参考文献：
  名称：

  Superbasic Amidine Monodentate Ligands in fac-[Re(CO)₃(5,5′-Me₂bipy)(Amidine)]BF₄ Complexes: Dependence of Amidine Configuration on the Remote Nitrogen Substituents

  摘要：

  Addition of various RNH2 to fac-[Re(CO)(3)(5,5'-Me(2)bipy)(CH3CN)]BF4 (1) converts the acetonitrile ligand to the amidine ligand (a superbase) in fac[Re(CO)3(5,5'-Me(2)bipy)(HNC(CH3)NHR)]BF4 products. Each complex has four conceivable isomers (E, E', Z, and Z') because the amidine CN bonds have double-bond character, and the two remote NHR group substituents are different. The reaction of 1 in acetonitrile is complete in 6 to 96 h (25 degrees C) and forms fac[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH3)NHR)]BF4 E' and Z isomers. Only the E' isomer formed crystals (R = methyl, isopropyl, isobutyl, tert-butyl, and benzyl). Upon dissolution of such crystals in acetonitrile-d(3), NMR spectra with highly dominant E' signals gradually changed (similar to 15 mm at room temperature) to spectra with signals for an equilibrium mixture of E' and Z isomers. Such slow E'-to-Zisomer interchange is also indicated by 2D ROESY NMR data used primarily to assign solution structure. Equilibrium ratios (E':Z) of similar to 65:35 for R = methyl, isopropyl, and isobutyl and 83:17 for R = tert-butyl demonstrate that increasing the remote NHR group steric bulk above a threshold size favors the E isomer. Consistent with this trend, fac-[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH3)NH2)BF4, with a remote NH2 (low bulk) group, favors the Z isomer. In contrast, although the remote NH(benzyl) group in fac-[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH3)NH(CH2C6H5)BF4 has only moderate bulk, the E isomer has high abundance as a result of favorable 5,5'-Me(2)bipy/benzyl stacking, evidence for which is present in both solid and solution states. The fac-[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH3)NHR)]BF4 E isomer can be detected in solvents of low polarity. However, the Z isomer was not observed, undoubtedly because unfavorable remote-group clashes with the equatorial ligands destabilize this isomer. Challenge studies with a 5-fold excess of 4-dimethylaminopyridine in acetonitrile-d(3) establish that fac[Re(CO)(3)(5,5'-Me(2)bipy)(HNC(CH3)NHCH(CH3)(2)]BF4 is robust because the isopropylamidine ligand was not displaced, consistent with the superbase character of amidine ligands.

  DOI：

  10.1021/ic100714m