CARBONYLATION (HYDROFORMYLATION AND HYDROCARBALKOXYLATION) REACTIONS IN THE PRESENCE OF TRANSITION-METAL - P-TERT-BUTYL-CALIX[4]ARENE-BASEDPHOSPHINE AND PHOSPHINITE SYSTEMS

In this study, etrakis(2-diphenylphosphinoxy-ethoxy)calix[4]arene (5) and -tetrakis(2-diphenylphosphinoethoxy)-calix[4]arene (6), as well as their platinum and palladium complexes (PtCl2)(2)(5), (PdCl2)(2)(5) w ere synthesised and characterised. In addition to these transition met al-containing complexes the catalytic systems formed in situ, from cat alytic precursors PtCl2(PhCN)(2), [Rh(nbd)Cl](2) and PdCl2(PhCN)(2) an d the corresponding calixarene ligand, were tested as catalysts in hyd roformylation and hydrocarbalkoxylation, respectively. High chemoselec tivity was obtained in hydroformylation in the presence of rhodium-con taining catalysts both with the above calixarene-based phosphine and p hosphinite ligands. The regioselectivity towards branched aldehyde sho ws a strong temperature dependence in case of phosphinite derivative. Although the platinum-containing systems show much lower catalytic act ivity, the regioselectivities are undoubtedly higher than those obtain ed with PtCl2(diphosphine)-SnCl2 systems. (C) 1998 Elsevier Science S. A. All rights reserved.