Organometallic chemistry with phosphines presenting unconventional coordination modes

Abstract

In this work, two differentiated blocks about the synthesis of complexes containing phosphine ligands presenting unconventional coordination modes are described. Following and adapting methods from literature, chelated palladium(II) complexes with general formula [Pd(3-2-methylallyl)(P*RR’CH2POR2- 2P*,O)](PF6) were synthesized. Starting from BH3-Pa, a P-stereogenic phosphine, chiral mono-oxidized diphosphine ligands were prepared and subsequently coordinated to Pd(II) centres by the splitting of a dimer complex of Pd(II), D0, resulting in two isomers of Pda. The corresponding chelated complexes were obtained from Pda, using halide scavengers to force the P*P(O) ligand to act as a bidentate, resulting in a five-membered ring metallocyclic cationic complexes, PdOa, which also presented two isomersThe synthesized ligands and complexes were characterized by 31P, 31P {1H} and 1H NMR. In the second part, the synthesis of four ruthenium complexes with general formula [RuCl2(6-arene)(P(PhPyr)R2)] and their derived two tethered complexes are described. 1-pyrenyl boronic acid was used as starting material to synthesize two phosphine ligands, PaPhPyr and PbPhPyr, which were coordinated to ruthenium centres by the splitting of two different metallic precursors, D1 and D2, obtaining Ru1a, Ru2a, Ru1b and Ru2b. Later, the corresponding tethered complexes were prepared under mild conditions by means of photochemical processes when they were just exposed to light of a common office lamp at room temperature, obtaining Rua’ and Rub’.The ligands and the complexes were characterized by 31P, 31P {1H}, 1H, 13C and 13C-1H gHSQC NMR, EA and HRMS, and also by XRD when it was possible.