Two 1,1′-azaphospha substituted dppf-analogues Fc′(NMe_(2))(PPh_(2))(Ph=C_(6)H_(5),Fc′=1,1′-ferrocenediyl,3a)and Fc′(NMe_(2))(PMes_(2))(Mes=_(2),4,6-Me_(3)C_(6)H_(2),3b)have been prepared,via reductive amination,...Two 1,1′-azaphospha substituted dppf-analogues Fc′(NMe_(2))(PPh_(2))(Ph=C_(6)H_(5),Fc′=1,1′-ferrocenediyl,3a)and Fc′(NMe_(2))(PMes_(2))(Mes=_(2),4,6-Me_(3)C_(6)H_(2),3b)have been prepared,via reductive amination,followed by salt-metathesis(of 2),starting from 1,1′-azabromoferrocene 1.Their donor properties have been explored using heteronuclear NMR spectroscopy based on their^(1)JP-Se coupling,and the formation of PdCl_(2)-complexes in comparison to a set of related dppf analogs with gradual steric variation,such as Fc′(PMes_(2))(PPh_(2))(5)and Fc′(PMes_(2))(PtBu_(2))(6).Chloride abstraction from these complexes,namely Fc′(PMes_(2))(PPh_(2))·PdCl_(2)(7),Fc′(PMes_(2))(PtBu_(2))·PdCl_(2)(8),and[Fc′(NMe_(2))(PPh_(2))]_(2)·PdCl_(2)(9)using AgSbF_(6)produced the corresponding cationic Pd(II)complexes[Fc′(PMes_(2))(PtBu_(2))·PdCl][SbF_(6)](10),[Fc′(PPh_(2))(NMe_(2))·PdCl][SbF_(6)]_(2)(11)and[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(2)C_(5)H_(5))][SbF_(6)]_(2)(1_(2))featuring Fe→Pd interactions.Variation of the counter anion by coordination of 3a to a chloride-free Pd(II)source furnished[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(3))][BF_(4)]_(2)(13),[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(2))Fc′(NMe_(2))][BF_(4)]_(2)(14),and[Fc′(PPh_(2))(NMe_(2))·PdP(p-OMe-C_(6)H_(4))_(3)][BF_(4)]_(2)(15)with similar Fe→Pd interactions.Comparison with previously reported diphospha-and azaphospha-counterparts,revealed that 10 and 11 display the shortest and 15 the longest Fe-Pd bond,within their ligand scaffold congeners.DFT calculations performed on compounds 10-15 were further able to verify their intrinsic structural features and trends and shed light on the nature of the Fe→Pd bonding interactions which are furthermore consistent with CV measurements.展开更多
基金financial support.Z.K.is grateful for the general support of János Bolyai Research Scholarship,Project UNKP-22-5-BME-298 and TKP2021-EGA-02 provided by the Ministry of Innovation and Technology of Hungary.
文摘Two 1,1′-azaphospha substituted dppf-analogues Fc′(NMe_(2))(PPh_(2))(Ph=C_(6)H_(5),Fc′=1,1′-ferrocenediyl,3a)and Fc′(NMe_(2))(PMes_(2))(Mes=_(2),4,6-Me_(3)C_(6)H_(2),3b)have been prepared,via reductive amination,followed by salt-metathesis(of 2),starting from 1,1′-azabromoferrocene 1.Their donor properties have been explored using heteronuclear NMR spectroscopy based on their^(1)JP-Se coupling,and the formation of PdCl_(2)-complexes in comparison to a set of related dppf analogs with gradual steric variation,such as Fc′(PMes_(2))(PPh_(2))(5)and Fc′(PMes_(2))(PtBu_(2))(6).Chloride abstraction from these complexes,namely Fc′(PMes_(2))(PPh_(2))·PdCl_(2)(7),Fc′(PMes_(2))(PtBu_(2))·PdCl_(2)(8),and[Fc′(NMe_(2))(PPh_(2))]_(2)·PdCl_(2)(9)using AgSbF_(6)produced the corresponding cationic Pd(II)complexes[Fc′(PMes_(2))(PtBu_(2))·PdCl][SbF_(6)](10),[Fc′(PPh_(2))(NMe_(2))·PdCl][SbF_(6)]_(2)(11)and[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(2)C_(5)H_(5))][SbF_(6)]_(2)(1_(2))featuring Fe→Pd interactions.Variation of the counter anion by coordination of 3a to a chloride-free Pd(II)source furnished[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(3))][BF_(4)]_(2)(13),[Fc′(PPh_(2))(NMe_(2))·Pd(PPh_(2))Fc′(NMe_(2))][BF_(4)]_(2)(14),and[Fc′(PPh_(2))(NMe_(2))·PdP(p-OMe-C_(6)H_(4))_(3)][BF_(4)]_(2)(15)with similar Fe→Pd interactions.Comparison with previously reported diphospha-and azaphospha-counterparts,revealed that 10 and 11 display the shortest and 15 the longest Fe-Pd bond,within their ligand scaffold congeners.DFT calculations performed on compounds 10-15 were further able to verify their intrinsic structural features and trends and shed light on the nature of the Fe→Pd bonding interactions which are furthermore consistent with CV measurements.
