SYNTHESIS AND STRUCTURAL STUDY OF [(PD(CH2C9H6N))2(MU-O2CR)-(MU-X)] COMPLEXES (R=ME OR CF3 X=HYDROXIDE, AMIDE OR THIOLATE)

The di-mu-carboxylato complexes [{Pd(CH2C9H6N)(mu-O2CR)}2] (CH2C9H6N = 8-quinolylmethyl, R = Me or CF3) react in methanol with NaOH(aq) (1:1 molar ratio) to give the corresponding mixed hydroxocarboxylato-bridged complexes [{Pd(CHC9H6N)}2(mu-OH)(mu-O2CR)] (R = Me 1 or CF3 2). The reactions of 1 or 2 with arylamines or thiols (1:1 molar ratio) yielded the corresponding amido- or thiolato-carboxylato complexes [{Pd(CH2C9H6N)}2(mu-O2CMe)(mu-NHR)] (R = Ph 3, p-MeC6H4 4 or p-NO2C6H4 5) or [{Pd(CHC9H6N)}2(mu-O2CR)(mu-SR')] (R = Me, R' = Et 6, Bu(t) 7, Ph 8 orp-MeC6H4 9; R = CF3, R' = Bu(t) 10). The H-1 NMR data indicate a cis arrangement of the CH2C9H6N ligands. The crystal structure of complex 10 has been determined. It confirms the cis relationship of the CH2C9H6N ligands. The co-ordination at each palladium atom is approximately square planar and the oxygen atoms of the trifluoroacetate ligands are trans to carbon. The Pd2(mu-OCOCF3)(mu-SBu(t)) core is quite bent with an angle of 55-degrees between the two palladium co-ordination planes.