Novel cyclopalladated ferrocenyl Schiff base compounds with bridging and chelating diphosphines. Crystal and molecular structure of [{Pd[(η5-C5H5)Fe(η5-C5H3)C(H)N-2,4,6-Me3C6H2]}{Ph2P(CH2)nPPh2P,P}][PF6] (n=1, 2)

The reaction of the ferrocenylimine (η5-C5H5)Fe(η5-C5H4)C(H)NR (R=2,4,6-Me3C6H2) (a), with Pd(AcO)2 or with Li2[PdCl4] leads to the heterotetrametallic compounds [Pd{(η5-C5H5)Fe(η5-C5H3)C(H)NR}(μ-O2CMe)]2 (1) and [Pd{(η5-C5H5)Fe(η5-C5H3)C(H)NR}(μ-Cl)]2 (2), respectively. Compound 2 may also be obtained by treatment of 1 with aqueous sodium chloride. Compound 2 reacts with tertiary diphosphines in 1:1 or 1:2 molar ratio to give [{Pd[(η5-C5H5)Fe(η5-C5H3)C(H)NR]Cl}2{μ-Ph2P(CH2)nPPh2}] (n=1, 3; n=2, 4; n=3, 5; n=4, 6), [{Pd[(η5-C5H5)Fe(η5-C5H3)C(H)NR]Cl}2(μ-Ph2PC5H4FeC5H4PPh2)] (7), and [Pd{(η5-C5H5)Fe(η5-C5H3)C(H)NR}{Ph2P(CH2)nPPh2P,P}][PF6] (n=1, 8; n=2, 9; n=3, 10; n=4, 11), [Pd{(η5-C5H5)Fe(η5-C5H3)C(H)NR}(Ph2PC5H4FeC5H4PPh2P,P)][PF6] (12), respectively. The crystal structures of compounds 8 and 9 have been determined by X-ray crystallography.