Synthesis, characterisation and reactivity towards PdII and PtII of ortho-, meta- and para-xylyl-based phosphorus-containing macrocycles

The new meta- and para-xylyl-based phosphadithiamacrocycles 6-phenyl-6-phospha-3,9-dithiabicyclo[9,3,1]pentadeca-1(15),12,14-triene (L2) and 6-phenyl-6-phospha-3,9-dithiabicyclo[9,2,2]pentadeca-1(13),12,14-triene (L3) have been synthesised and characterised. The reactivity of these ligands and the previously described ortho-xylyl macrocycle 6-phenyl-6-phospha-3, 9-dithiabicyclo [9,4,0]pentadeca-1(11), 12,14-triene (L1) with [PdCl2(cod)] and K-2[PtCl4] has been studied. [MCl2(L)] complexes have been obtained and characterised by NMR spectroscopy. X-ray structural analyses have been carried out in the case of [PdCl(2)L2].CH3CN (2.CH3CN) and [PdCl(2)L3] (3). In both compounds the Pd-II ion adopts a slightly distorted square-planar coordination defined by one S-thioether, the P-phosphane atoms of the ligand and two chlorine atoms, which are oriented in a mutual cis position, whereas the second S-thioether atom of the ligand remains uncoordinated. According to the spectroscopic data, the same coordination mode is found for the Pt-II complexes. (C) Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.