Silver decoration of a palladacycle through "spacer-guest" interaction

Abstract

[Pd(dppf)(MeCN)2](OTf)2 [dppf = 1,1′-bis(diphenylphosphino)ferrocene, OTf = triflate] reacts with pyridyl acetic acid (PyAcOH) to yield a dipalladium ring structure, [Pd2(dppf)2(μ-PyOAc)2](OTf)2 (1). The doubly-bridging ligands exhibit basicity at the pendant carboxyl oxygen to attract AgX (X = OTf or CF3CO2) to form [Pd2Ag2(dppf)2(PyOAc)2(OTf)4] (2) and [Pd2Ag2(dppf)2(PyOAc)2(OTf)2(CF3CO2)2] (3), respectively. Complexes 1 and 2 have been crystallographically characterized. Similar spacer-guest affinity is not found in the Pt(II) or isonicotinate analogues. © 2005 Elsevier B.V. All rights reserved.