Anion-recognition of an Ionic Cyclodimeric Pd(II) Complex

Abstract

Ionic macrocyclodimeric palladium(II) complex, [(dppp)Pd(m-pmps)]2(CF3SO3)4 (dppp=1,3-bis(diphenylphosphino)propane; m-pmps¼1,3-bis(3-pyridyl)-1,3-dimethyl- 1,3-diphenyldisiloxane), was synthesized and its molecular structure determined by X-ray single crystallography. The complex has 19 rings consisting of one 20-membered metallamacrocycle, 2 six-membered metallacycles, 4 pyridyl groups, and 12 phenyl groups. The local geometry around palladium(II) approximates to a typical square planar arrangement with two cis phosphines (P–Pd–P¼90.54(7)˚; N–Pd–N¼84.6(2)˚; Pd–P¼2.259(2)A˚ , 2.270(2)A˚ ; Pd–N=2.100(5)A˚ , 2.112(5)A˚ ). The triflates were smoothly exchanged to produce [(dppp)Pd(m-pmps)]2(X)4 (X-¼NO-4 , ClO-4 , BF-4 , PF-6 , and SbF-6 ; (X)2¼SO2-4 and MoO2-4 ). According to 1H-NMR chemical shifts and conductivity measurements, the macrocyclodimer was sensitive to the Hoffmeister series of anions.