U. Fekl, W. Kaminsky, K.I. Goldberg. A stable Five- Coordinate platinum(IV) alkyl complex. J Am. Chem. Soc. 123 (2001) 6423-6424.

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see further R.J. Puddephatt: Coordinative Unsaturation in Platinum(IV) Vhemistry: From Proposed reaction Intermediates to the First Structuarally Characterized Complexes. Angew. Chem. Int. Ed. 41 (2002) 261-263