TRANSITION-METAL COMPLEXES OF LOWER RIM 1,3-DIPHOSPHINITE AND 1,3-DIPHOSPHINO CALIX[4]ARENES

5,11,17,23-Tetra-tert-butyl-25,27-bis((diphenylphosphino)oxy)-26,28-dipropoxycalix[4]arene, 3, is easily prepared from chlorodiphenylphosphine and 1,3-dipropoxycalix[4]arene in exclusively the cone conformation. 5,11,17,23-Tetra-tert-butyl-25,27-bis((diphenylphosphino)ethoxy)-26,28-dipro poxycalix[4]arene, 5 (also in the cone conformation), is obtained from the reaction of KPPh(2) with the 1,3-ditosylate calix[4]arene derivative. The coordination properties of calix[4]arene ligands 3 and 5 with Rh-I, Cu-I, and Pt-II have been investigated. Isolation of both bimetallic (Rh-2(3)(COD)(2)Cl-2) and monometallic (Rh(3(P=O))(COD)CI) complexes proved that the ligand binds to the Rh-I ion in a monodentate fashion. However, in the case of the Cu-I complex, a bidentate coordination is observed. Compound 5 coordinates to both Cu-I and Pt-II in a bidentate fashion, in which the two phosphorus atoms coordinate in a cis arrangement to the Pt-II center.