REACTIONS OF RHODIUM PORPHYRINS WITH LACTONES, SILANES, AND STANNANES

(2,3,7,8,12,13,17,18-Octaethylporphyrinato)rhodium(I) (Rh(I)OEP) cleaved the alkyl-oxygen bond of four-membered-ring and five-membered-ring lactones (beta-propiolactone (1), beta-butyrolactone (2), and gamma-butyrolactone (3)) at room temperature to regioselectively yield (omega-carboxyalkyl)Rh(III)OEP. [{Rh(II)OEP}(2)] reacted with R(2)(1)R(2)MH (8, M = Si, R(1) = R(2) = Et; 9, M Si, R(1) = R(2) = Ph; 10, M = Si, R(1) = Me, R(2) = Ph; 11, M = Si, R(1) = Me, R(2) = Oet; 16, M = Sn, R(1) = R(2) = Bu; 17, M = Sn, R(1) = R(2) = Ph) to yield Rh-III(MR(2)(1)R(2))OEp. These alkyl-, silyl-, and stannylrhodium complexes of OEP were characterized by H-1, C-13, Si-29, and Sn-119 NMR, IR, UV-vis, and mass spectroscopy. (triethylsilyl)Rh(III)OEP crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 17.14(8) Angstrom, b = 14.94(5) Angstrom, c = 31.22(5) Angstrom, and beta = 103.5(2)degrees; the density is 1.28 g/cm(3) for Z = 8. The porphyrin plane is almost planar, and the rhodium metal resides on the plane. The Rh-Si distance is 2.32(1) A, and dl the eight ethyl groups on the pyrroles are directed toward the triethylsilyl group. The present method has proved to be a facile way to prepare bimetallic rhodium complexes of porphyrin.