A diamagnetic ruthenium(II) complex of 5,10,15,20-tetraphenyl-p-benziporphyrin [Ru-II(p-BzP)(CO)Cl] was obtained via the insertion of ruthenium into p-benziporphyrin triruthenium(0) dodecacarbonyl [Ru-3(CO)(12)] as the metal source. The procedure applying dichloro(cycloocta-1,5-diene)ruthenium(II) (polymer, [Ru(COD)Cl-2](n)) afforded the paramagnetic six-coordinate ruthenium(III) p-benziporphyrin [Ru-III(p-BzP)Cl-2]. As shown by X-ray crystallography, the p-phenylene ring in both complexes is sharply tilted out of the N-3 plane, as reflected by the respective N-3 (pyrrole)-C-6 (p-phenylene) dihedral angle [Ru-II(p-BzP)(CO)Cl, 52.5 degrees; Ru-III (p-BzP)Cl-2, 53.7 degrees]. p-Phenylene is bound to the ruthenium cation in an eta(2) fashion, revealing the shortest ever Ru-C distance in the series of p-benziporphyrin complexes [Ru-II(p-BzP)(CO)Cl, 2.275(2) angstrom; Ru-III(p-BzP)Cl-2, 2.324(5) angstrom]. The reaction of Ru-II(p-BzP)(CO)Cl with ArMgCl or AlkMgCl results in the formation of diamagnetic six-coordinate ruthenium(II) p-benziporphyrin complexes containing the apically coordinated sigma-alkyl or sigma-aryl ligands, where the metal ion simultaneously coordinates to three carbon centers respectively accommodating eta(2) (phenylene) and sigma (aryl and alkyl) modes. Reactions of sigma-aryl (alkyl) carbanions with paramagnetic Ru-III(p-BzP)Cl-2 have been followed by H-1 NMR spectroscopy. The procedure afforded the six-coordinate paramagnetic ruthenium(III) p-benziporphyrin [Ru-III(p-BzP)(Ph)Cl], which binds one sigma-aryl ligand, as reflected by the characteristic H-1 NMR spectra spread within the +120 to -120 ppm range. Both paramagnetic complexes Ru-III(p-BzP)(Ph)Cl and Ru-III(p-BzP)(p-Tol)Cl are formed as a mixture of two stereoisomers differentiated by two nonequivalent locations of sigma-aryl with respect to the puckered macrocyclic ring. The paramagnetic shifts of sigma-aryls are indicative of pi-spin delocalization patterns. Analysis of the contact shifts and parallel density functional theory calculations of the spin density distribution in Ru-III(p-BzP)Cl-2, Ru-III(p-BzP)(Ar)Cl, and Ru-III(p-BzP)(Alk)Cl reflect the features of the d(xy)(2)(d(xz)d(yz))(3) electronic ground state.