PREPARATION AND STRUCTURES OF 2 STERICALLY PROTECTED RUTHENIUM PORPHYRIN COMPOUNDS OF THE TYPE-RU(POR)(H2O)(IN)(CO)(OUT)

Abstract

Two sterically protected ruthenium porphyrin compounds of the type Ru(Por)(H2O)in(CO)out have been prepared, and their structures have been determined by single-crystal X-ray diffraction methods. Both compounds, Ru(beta-PocPivP)(H2O)in(CC)out (1), a ''pocket'' porphyrin, and Ru(OCCOPor)(H2O)in(CO)out (2), a ''capped'' porphyrin, pack as discrete porphyrin units with solvate molecules. In both compounds, the H2O ligand is inside the sterically protected region while the CO ligand is trans to the H2O molecule and is on the outside of the protected region. In Ru(beta-PocPivP)(H2O)in(CO)out, the H2O ligand is hydrogen-bonded to an amide oxygen atom, the O(H2O)-O(amide) distance being 2.688(4) angstrom; in Ru(OCCOPor)(H2O)in(CO)out, the H2O ligand, though not involved in traditional hydrogen bonding, may interact with the aromatic pi system of the benzene cap, the O(H2O)-cap centroid distance being 2.98 angstrom. The carbonyl groups have their normal, linear arrangement, with the Ru-C-O angles being 178.7(3) and 178.1(4)degrees in 1 and 2, respectively. In each structure, the porphyrin plane is slightly ruffled, with the Ru atom lying 0.20 and 0.26 angstrom below the porphyrin plane toward the carbonyl group in 1 and 2, respectively. In each structure, the cap is off-center and tilted. Each cap centroid lies 4.25 (1) and 4.79 A (2) above the porphyrin plane. These structures provide some useful insights info steric constraints in these encumbered porphyrins. Crystallographic data for Ru(beta-PocPivP)(H2O)in(CO)out.2CHCl3 (1): triclinic, C(i)l-P1BAR, Z = 2, a = 13.261(3) angstrom, b = 14.450(3) angstrom, c = 15.716(3) angstrom, alpha = 91.63(3)degrees, beta = 94.94(3)degrees, gamma = 94.40(3)degrees, 1 = -167-degrees-C, 11 611 unique reflections, 805 variables, R(F( (F(o))2 > 2sigma(F(o)2)) = 0.045, R(w)(F2) = 0.101. Crystallographic data for Ru(OCCOPor)-(H2O)in(CO)out-2CHCl3-1/2n-C6H12 (2): triclinic C(i)l-P1BAR, Z = 2, a = 9.651(2) A, b = 11.936(2) angstrom, c = 25.964(5) angstrom, alpha = 92.14(3)degrees, beta = 91.58(3)degrees, gamma = 104.99(3)degrees, t = -167-degrees-C, 15 970 unique reflections, 760 variables, R(F) (F(o)2 > 2sigma(F(o)2)) = 0.086, R(w)(F2) = 0.183.