| Summary: | Treatment of the double nuclear complex <b>1a</b>, di-μ-cloro-bis[N-(4-formylbenzylidene)cyclohexylaminato-C6, N]dipalladium, with Ph<sub>2</sub>PCH<sub>2</sub>CH<sub>2</sub>)<sub>2</sub>PPh (triphos) and NH<sub>4</sub>PF<sub>6</sub> gave the single nuclear species <b>2a</b>, 1-N-(cyclohexylamine)-4-N-(formyl)palladium(triphos)(hexafluorophasphate). Reaction of <b>2a</b> with Ph<sub>2</sub>PCH<sub>2</sub>CH<sub>2</sub>NH<sub>2</sub> in refluxing chloroform via a condensation reaction of the amine and formyl groups to produce the C=N double bond, gave <b>3a</b>, 1-N-(cyclohexylamine)-4- N-(diphenylphosphinoethylamine)palladium(triphos)(hexafluorophasphate); a potentially bidentate [<i>N</i>,<i>P</i>] metaloligand. However, attempts to coordinate a second metal by treatment of 3a with [PdCl<sub>2</sub>(PhCN)<sub>2</sub>] were to no avail. Notwithstanding, complexes <b>2a</b> and <b>3a</b> left to stand in solution spontaneously self-transformed to give in either case the double nuclear complex <b>10</b>, 1,4-N,N-terephthalylidene(cyclohexilamine)-3,6-[bispalladium(triphos)]di(hexafluorophosphate), after undergoing further metalation of the phenyl ring, then bearing two mutually <i>trans</i> [Pd(Ph<sub>2</sub>PCH<sub>2</sub>CH<sub>2</sub>)<sub>2</sub>PPh)-<i>P</i>,<i>P</i>,<i>P</i>] moieties: an unprecedented and serendipitous result indeed. On the other hand, reaction of the double nuclear complex 1b, di-μ-cloro-bis[N-(3-formylbenzylidene)cyclohexylaminato-C6, N]dipalladium, with Ph<sub>2</sub>PCH<sub>2</sub>CH<sub>2</sub>)<sub>2</sub>PPh (triphos) and NH<sub>4</sub>PF<sub>6</sub> gave the single nuclear species <b>2b</b>, 1-N-(cyclohexylamine)-4-N-(formyl)palladium(triphos)(hexafluorophasphate), Treatment of <b>2b</b> with H<sub>2</sub>O/glacial MeCOOH gave cleavage of the C=N double bond and of the Pd···N interaction, yielding <b>5b</b>, isophthalaldehyde-6-palladium(triphos)hexafluorophosphate, which then reacted with Ph<sub>2</sub>P(CH<sub>2</sub>)<sub>3</sub>NH<sub>2</sub> to yield complex <b>6b</b>, N,N-(isophthalylidene(diphenylphosphinopropylamine)-6-(palladiumtriphos)di(hexafluorophosphate), with two pairs of non-coordinated nitrogen and phosphorus donor atoms. Treatment of <b>6b</b> with [PdCl<sub>2</sub>(PhCN)<sub>2</sub>], [PtCl<sub>2</sub>(PhCN)<sub>2</sub>], or [PtMe<sub>2</sub>(COD)] gave the new double nuclear complexes <b>7b</b>, <b>8b</b> and <b>9b</b>, palladiumdichloro-, platinumdichloro- and platinumdimethyl[N,N-(isophthalylidene(diphenylphosphinopropylamine)-6-(palladiumtriphos)(hexafluorophosphate)-P,P], respectively, showing the behavior of <b>6b</b> as a palladated bidentate [<i>P</i>,<i>P</i>] metaloligand. The complexes were fully characterized by microanalysis, IR, <sup>1</sup>H, and <sup>31</sup>P NMR spectroscopies, as appropriate. The X-ray single-crystal analyses for compounds 10 and 5b have been previously described as the perchlorate salts by JM Vila et al.
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