Effect of pnictogen ligand substitution on a tripalladium ditropylium core.
A combination of multinuclei NMR, UV-vis spectroscopy, and single crystal X-ray diffraction was used to characterize a new series of tripalladium ditropylium sandwich complexes [Pd(3)Tr(2)(E)(3)][BF(4)](2) (E = PPh(3), AsPh(3), and SbPh(3) and PEt(3)). Ligand substitution leads to a systematic shift of the (1)H and (13)C NMR tropylium resonances and is correlated with the electron donating properties of the substituent group. Replacement of the ligand increases the palladium-pnictogen bond length in the order P < As < Sb; however, this only slightly alters the internal Pd-Pd bond lengths, supporting the hypothesis that there are only weak Pd-Pd bonding interactions.
Babbini
Dominic C
DC
Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, Arizona 86011-5698, USA.
Mulligan
Frank L
FL
Schulhauser
Hannah R
HR
Sweigart
Tara C
TC
Nichol
Gary S
GS
Hurst
Stephanie K
SK