204455-50-5Relevant academic research and scientific papers
Different Degrees of Electron Delocalization in Mixed Valence Ru-Ru-Ru Compounds by Cyanido-/Isocyanido-Bridge Isomerism
Yang, Yu-Ying,Zhu, Xiao-Quan,Hu, Sheng-Min,Su, Shao-Dong,Zhang, Lin-Tao,Wen, Yue-Hong,Wu, Xin-Tao,Sheng, Tian-Lu
, p. 14046 - 14050 (2018)
The two stable pairs of trimetallic compounds trans-[Cp*(dppe)Ru(μ-NC)Ru(dmap)4(μ-CN)Ru(dppe)Cp*][PF6]n (1[PF6]n, n=2, 3; Cp=1,2,3,4,5-pentamethylcyclopentadiene; dppe=1,2-bis-(diphenylphosphino)ethane; dmap= 4-dimethylaminopyridine) and trans-[Cp*(dppe)Ru(μ-CN)Ru(dmap)4(μ-NC)Ru(dppe)Cp*][PF6]n (2[PF6]n, n=2, 3), which demonstrate cyanide/isocyanide isomerism, have been synthesized and fully characterized. 13+[PF6]3 and 23+[PF6]3 are the one-electron oxidation products of 12+[PF6]2 and 22+[PF6]2, respectively. The results suggest that 1[PF6]3 is a class III mixed valence compound, whereas 2[PF6]3 might be an unusually symmetrical class II–III mixed valence compound composed of the two asymmetrical delocalized RuIII?NC?RuII mixed valence subunits.
Cyanide Ligand Basicities in Cp′M(L)2CN Complexes (M = Ru, Fe). Correlation between Heats of Protonation and vCN
Nataro, Chip,Chen, Jiabi,Angelici, Robert J.
, p. 1868 - 1875 (2008/10/08)
Basicities of the cyanide ligands in a series of Cp′M(L)2CN complexes were investigated by measuring their heats of protonation (-δHCNH) by CF3SO3H in 1.2-dichloroethane solution at 25.0 °C to give Cp′M(L)2(CNH)+CF3SO3 -, in which the N-H+ group is probably hydrogen-bonded to the CF3SO3- anion. Basicities (-δHCNH) of the CpRu(PR3)2CN complexes increase from 20.5 (PPh3) to 22.4 (PMe3) kcal/mol with increasing donor abilities of the phosphine ligands. Basicities of all the Cp′Ru(PR3)2CN complexes, where Cp′ = Cp or Cp*, are linearly correlated with their vCN values; the nonphosphine complexes. CpRu(l.10-phen)CN and CpRu(COD)CN, do not follow the same correlation. For a large number of Cp′M(L)2CN complexes (M = Ru, Fe, L2 = mono- and bidentate phosphines, CO, 1,10-phen, and COD), their vCN values parallel vCN values of their protonated Cp′M(L)2(CNH)+ analogues. Also, 31P NMR chemical shifts of the unprotonated Cp′M(PR3)2-CN and protonated CpM(PR3)2(CNH)+ complexes are linearly related. Despite the high basicity of Ru in Cp*Ru-(PMe3)2Cl (30.2 kcal/mol), the CN- in Cp*Ru(PMe3)2CN (25.0 kcal/mol) is the site of protonation: factors that determine whether protonation occurs at the Ru or the CN- are discussed.
