Survey of Known Five-Coordinate Pt IV Complexes

Following the first reports of isolable five-coordinate Pt(lV) species, several other stable five-coordinate Pt(lV) species have been prepared and characterized. These complexes are illustrated in Fig. 4 [89-99]. 

The Pt(IV) silyl complexes 2a-c, 5a-c, 6, and 7a-b are not fluxional on the NMR time scale, and exist solely as the isomers with the silyl group trans to the open site [84, 91, 96-98]. This rigidity could be attributable to steric factors and/or the high transinfluence of the silyl group. 

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