New building blocks for the noncovalent assembly of homo- and hetero-multinuclear metallodendrimers

Ligands 5 and 8, derived from the coupling of [3,5-bis[(diphenylphosphinyl)methyl]phenyl] oxy groups to bi- and trifunctional spacers, respectively, were cyclometalated with Pd[CH3CN](4)(BF4)(2), cis-[PtCl2(PPh3)(2)], or NiCl2 . 6H(2)O. The cationic Pd and Pt complexes were converted into overall neutral Pd-Cl and Pt-Cl complexes. The resulting pincer complexes can be used as building blocks for the controlled assembly of both homo- and hetero-multinuclear metallodendrimers. The P-31 NMR spectra of the pincer complexes exhibit different shifts for chloride, H2O, or nitrile occupying the fourth coordination site, making the P-31 chemical shift an excellent diagnostic tool for the assembly process.