Non-trivial behavior of palladium(II) acetate.
Reaction of activated palladium metal with a HNO3/acetic acid mixture produces both orange Pd3(OAc)6, 1, and purple Pd3(OAc)5(NO2), 2. Compound has a trinuclear structure derived from that of the well-known triangular complex 1 in which one acetate group has been replaced by a nitrite group which is bonded to one palladium atom by the nitrogen atom and to another Pd atom using one of the oxygen atoms. Highly pure 1 can be made by continuous removal of the nitric oxides from the reaction mixture using a flow of N2. 1H NMR spectra of solutions of 1 in CDCl3 and C6D6 show several signals of various intensities when a small amount of water is present in the deuterated solvents but only one signal when the solvents are thoroughly dried. These results are consistent with the occurrence of one or more hydrolysis processes when the solvents contain water and suggest that hypotheses about various [Pd(OAc)2]n aggregates that have previously been brought forward in the literature to explain the complexity of the spectrum of 1 are unnecessary, especially for nonpolar solvents. Compound 2 does not hydrolyze, and in wet or dried solvents shows a 1H NMR spectrum that consists of five equal-intensity signals due to the five nonequivalent acetate groups.
Bakhmutov
Vladimir I
VI
Laboratory for Molecular Structure and Bonding, Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, TX 77842-3012, USA.
Berry
John F
JF
Cotton
F Albert
FA
Ibragimov
Sergey
S
Murillo
Carlos A
CA
D000085:Acetates / Q000737:chemistry*; D002413:Cations, Divalent; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009569:Nitric Oxide / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D014867:Water / Q000737:chemistry
D000085:Acetates; D002413:Cations, Divalent; D009942:Organometallic Compounds; D012997:Solvents; D014867:Water; D009569:Nitric Oxide; D010984:Platinum