Rhodium complexes with secondary phosphine and phosphinite ligands and the crystal structures of [(PPh2OH)(2)(PPh2O)Rh(mu-Cl)(3)Rh(PPh2OH)(PPh2O)(2)] and [(PPh2OH)(PPh2O)Cl(NCMe)Rh(mu-Cl)(2)Rh(PPh2OH)(PPh2O)Cl(NCMe)]center dot 2thf

摘要

RhCl3. 3H(2)O reacts with ca six molar equivalents of PPh2H orPCy(2)H in EtOH solution under a N-2 atmosphere and in the presence of excess NH4PF6 to yield [RhCl2(PPh2H)(4)]PF6 or [RhCl2(PCy2H)(4)]PF6 respectively as yellow solids. P-31{H-1} NMR spectroscopy shows the presence of the trans isomer only in chlorocarbon solutions, with J(RhP) ca 80 Hz. Upon standing a solution of trans-[RhCl2(PPh2H)(4)]PF6 in a MeCN/thf mixture results in the production of yellow crystals of [(PPh2OH)(PPh2O)Cl(NCMe)Rh(mu-Cl)(2)Rh(PPh2OH) (PPh2O)Cl(NCMe)]. 2thf, the structure of which shows an edge-bridged bioctahedral arrangement with d(Rh ... Rh) = 3.74 Angstrom. The NCMe ligands lie trans to the terminal Cl ligands, while the PPh2OH and PPh2O- ligands are trans to the bridging Cl ligands. The crystal structure of the triply-bridged dimer [(PPh2OH)(2)(PPh2O)Rh(mu-Cl)(3)Rh(PPh2OH)(PPh2O)(2)] has also been determined, showing a face-sharing bioctahedral arrangement, with d(Rh ... Rh) = 3.39 Angstrom. Both dinuclear species show significant P-O-H ... O-P hydrogen-bonding interactions. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 26]