THE SYNTHESIS, X-RAY STRUCTURE, AND SUBSTITUTION LABILITY OF CHLORO(2,3,7,8,12,13,17,18-OCTAETHYLPORPHINATO)(TRIPHENYLPHOSPHINE)RHODIUM(III)

The rhodium(III) octaethylporphyrin complex Rh(OEP)(PPh3)Cl (1) has been synthesized via Rh(III) or Rh(I) precursors, and fully characterized both by spectroscopy and single crystal data. The crystals, available as a bis(chloroform) solvate are triclinic, P1, a = 13.478(5), b = 14.300(5), c = 15.346(4)A, a = 102.33(2), 13 102.89(2), y = 90.56(3)°, Z= 2, D = 1.384gcm3.The structure was determined from Mo diffractometer data and refined by least-squares methods to R = 0.095, R = 0.068 for 5189 reflections. The octahedrally coordinated rhodium atom is displaced by 0.07 7 A from the mean plane of the four N atoms, towards the triphenylphosphine group. The average Rh - ring nitrogen distance is 2.024 A, Rh-P is 2.306(3) A and Rh-Cl, 2.442(2) A. Solution equilibria studies on 1 describe formation of Rh(OEP)L2 (L = PPh3, PBu3) via thermal reactions (including thermodynamic data for the PPh3 system), and formation of Rh(OEP)Cl(L') species (L' = CO. THF, MeCN) via photochemical processes.