A variety of half-open ruthenocenes of the general formula Ru(C5Me5)(Pdl) have been prepared from [Ru(C5Me5)Cl]4. For C5H7 or alkylated or arylated pentadienyl groups (1-, 2-, or 3-C6H9; 2,3-C7H11; 2,4-C7H11; 1,5-(C6H5)2C5H5), their introductions were brought about by using their potassium salts. For the oxo dienyl analogues 2,4-OC6H9 or 3,5-OC6H9, the respective enone or enal could be utilized, which underwent deprotonation upon coordination in the presence of K2CO3. With HPdl = 2,4-(CF3)2C5H6, coordination is accompanied by the spontaneous elimination of HCl, yielding Ru(C5Me5)[2,4-(CF3)2C5H5]. A similar reaction led to Ru(C5Me4Et)[2,4-(CF3)2C5H5]. In addition to various spectroscopic studies, structural studies were carried out on the Pdl = 3-C6H9 and 3,5-OC6H9 complexes, as well as for Ru(C5Me4Et)[2,4-(CF3)2C5H5]. For the Pdl = 3-C6H9 complex, the space group is P2(1)/m with a = 7.598 (1) angstrom, b = 13.246 (2) angstrom, c = 7.526 (1) angstrom, beta = 96.429 (4)-degrees, and V = 752.7 angstrom 3 for Z = 2. For the oxo dienyl compound, the space group is P2(1)2(1)2(1), with a = 10.651 (2) angstrom, b = 11.925 (1) angstrom, c = 11.987 (2) angstrom, and V = 1522.4 angstrom 3 for Z = 4. For the 2,4-(CF3)2C5H5 compound, the space group is Cmc2(1) with a = 15.324 (3) angstrom, b = 8.785 (2) angstrom, c = 13.726 (2) angstrom, and V = 1847.8 angstrom 3 for Z = 4. The structures were refined to respective R (and R(w)) values of 0.026 (0.030), 0.034 (0.035), and 0.028 (0.031).
