Divalent bis(phosphinimino)methanide lanthanide complexes of composition [{(Me
3SiNPPh
2)
2CH}EuI(THF)]
2 and [{(Me
3SiNPPh
2)
2CH}YbI(THF)
2] have been prepared by a salt metathesis reactions of K{CH(PPh
2NSiMe
3)
2} and LnI
2. Further reactions of these complexes with [K(THF)
nN(PPh
2)
2] led selectively to the heteroleptic amido complexes [{(Me
3SiNPPh
2)
2CH}Ln{(Ph
2P)
2N}(THF)] (Ln = Eu, Yb). The ytterbium complex can also be obtained by reduction of [{CH(PPh
2NSiMe
3)
2}Yb{(Ph
2P)
2N}Cl] with elemental potassium. The single crystals of [{(Me
3SiNPPh
2)
2CH}Ln{(Ph
2P)
2N}(THF)] contain enantiomerically pure complexes. As a result of the similar ionic radii of the divalent lanthanides and the heavier alkaline earth metals some similarities in coordination chemistry of the bis(phosphinimino)methanide ligand were anticipated. Therefore, MI
2 (M = Ca, Sr, Ba) was reacted with K{CH(PPh
2NSiMe
3)
2} to give [{(Me
3SiNPPh
2)
2CH}CaI(THF)
2], [{(Me
3SiNPPh
2)
2CH}SrI(THF)]
2, and [{(Me
3SiNPPh
2)
2CH}BaI(THF)
2]
2, respectively. As expected the Sr and Eu complexes and the Ca and Yb complexes are very similar, whereas for the Ba compound, as a result of the large ion radius, a different coordination sphere is observed. For all new complexes the solid-state structures were established by single crystal X-ray diffraction. In the solid-state the {CH(PPh
2NSiMe
3)
2}
− ligand acts as tridentate donor forming a long methanide carbon metal bond. Thus, all complexes presented can be considered as organometallic compounds. [{(Me
3SiNPPh
2)
2CH}YbI(THF)
2] was also used as precatalyst for the intramolecular hydroamination/cyclization reaction of different aminoalkynes and aminoolefines. Good yields but moderate activities were observed.
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