Neue Zinkkomplexe mit Bis(phosphinimino)methan-Liganden (English shop)

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The monoanionic bisphosphiniminomethanide ligand {CH(PPh2NSiMe3)2}- is widely used in the organometallic chemistry of main group and transition metals as well as of the lanthanides.

Bisphosphiniminomethanide zinc complexes are characterised by an unusual reactivity of the ligand backbone towards electrophiles.

Thus, the reaction of in situ generated [Zn(BH4)2(THF)2] with the potassium salt of the ligand affords the heteroleptic boranate complex [{CH(PPh2NSiMe3)2}(?1-BH3)Zn(BH4)], in which a BH3 molecule coordinates in a capping fashion between the metal centre and the bridging carbon atom of the ligand. The complex can be obtained rationally from the reaction of [{CH(PPh2NSiMe3)2}ZnN(SiMe3)2] with BH3•THF, whereas the reaction of [{CH(PPh2NSiMe3)2}ZnMe] with BH3•THF yields the complex [{CH(PPh2NSiMe3)2}(?1-BH3)ZnMe]. The bonding situation in the bisphosphiniminomethanide zinc complexes was additionally investigated by means of quantum chemical calculations at the DFT level.

The heteroleptic complex [{CH(PPh2NSiMe3)2}ZnPh] is accessible from the reaction of the neutral ligand with the homoleptic zinc organyl ZnPh2. The reaction with heterocumulenes ((p-tolyl-N=)2C, Ph2C=C=O) leads to an addition to the ligand backbone instead of the expected insertion into the Zn-Ph bond.