FERROCYNE AND FERRODICYNE - PREPARATION AND STRUCTURES OF OS3(CO)9[MU-3-(C5H3)FE(C5H5)][MU-3-P(C5H4)FE(C5H5)], OS3(H)2(CO)8(PPRI2C5H2)FE(C5H2PPRI2)OS3(H)2(CO)8, AND OS3(CO)9[MU-3-C6H4][MU-3-P(C5H4)FE(C5H5)]

The thermolysis of Os3(CO)11PPhFc2 affords Os3(CO)9[mu(3)-aryne][mu(3)-P(C5H4)Fe(C5H5)] (aryne = ferrocyne, (C5H3)Fe(C5H5) (2), benzyme, C6H4 (6)). Likewise the ferrodicyne Fe(C5H3)2 derivative Os3(H)2(CO)8-(PPr2iC5H2)Fe(C5H2PPr2i)Os3(H)2(CO)8 (3) is obtained from Os3(CO)11(PPr2iC5H4)Fe(C5H4PPr2i)Os3(CO)11. In 2 the ferrocyne moiety is a symmetrical four-electron donor to an open Os3P cluster; in 6 the benzyne is an unsymmetrical donor of two to four electrons to the open Os3P cluster. In 3 each aryne ring acts as an unsymmetrical four-electron donor to a closed Os3 cluster that is also coordinated to the PPr2i group of the other aryne ring. Crystal data for 2.0.5CH2Cl2: triclinic, P1BAR, a = 12.638 (4) angstrom, b = 15.244 (5) angstrom, c = 9.867 (3) angstrom, alpha = 100.85 (2)-degrees, beta = 105.56 (2)-degrees, gamma = 69.80 (2)-degrees, Z = 2; final R = 0.028 (R(w) = 0.030) from 6180 observed reflections. Crystal data for 3: monoclinic, P2(1)/c, a = 13.607 (2) angstrom, b = 22.925 (6) angstrom, c = 16.649 (3) angstrom, beta = 113.00 (2)-degrees, Z = 4; final R = 0.031 (R(w) = 0.026) from 7034 observed reflections. Crystal data for 6: triclinic, P1BAR, a = 10.858 (3) angstrom, b = 13.960 (3) angstrom, c = 10.383 (3) angstrom, alpha = 95.54 (3)-degrees, beta = 110.98 (3)-degrees, gamma = 106.34 (2)-degrees, Z = 2; final R = 0.035 (R(w) = 0.040) from 6251 observed reflections.