SYNTHESIS AND STRUCTURE OF DI-u-ACETATOBIS [DICARBONYLPYRAZOLERUTHENIUM(I)] (RuRu) By C. H. Huang1, T. H. Lu1, W. M. Lee2 and K. B. Shiu2 1 Department of Physics, National Tsing Hua University, Hsinchu, Taiwan, 300; 2 Department of Chemistry, National Cheng Kung University, Tainan, Taiwan 701, Republic of China.
Nucleophilic substitution of [Ru2(CO)4(u-O2CMe)2(NCMe)22(CO)4(u-O2CMe)2(Hpz)2 .
X-ray srtucture of the compound was determined after crystal dimensions of 0.30 x 0.35 x 0.45 mm had been selected. The cell dimensions are a=8.332(1), b=9.5236(7), c=13.539(2) Å, [[alpha]]=90.020(8), [[beta]]=100.33(2), [[gamma]]=111.34(1)deg. with centrosymmetric space group of P 1 bar. The cell volume is 982.0(2) Å3 containing two molecules. Calculated density is 1.922 Mg m-3. The linear absorption coefficient of the crystal is 1.55 mm-1. Absorption corrections were made. The final R/Rw factors were 0.026/0.042 for 3886 reflections with I>2.5 [[sigma]](I) collected on a Nonius diffractometer, using the theta/ two theta scan mode.Weights based on counting-statistics were used. The maximum shift/sigma ratio was 0.001. In the last difference Fourier map, the deepest hole was -.54 e/Å3 and the highest peak 0.88 e/Å3. The secondary extinction coefficient is 0.13(2).The Ru-Ru distance is 2.6746(6) Å Both rutheniums have six bonds. The distances of Ru-O range from 2.110(2) to 2.136(2) Å, those of Ru-C span from 1.822(3) to 1.829(3) Å and those of Ru-N from 2.203(2) to 2.205(3) Å. The intramolecular hydrogen bonds of N2-H....O4 and N4H....O6 are 2.790(3) and 2.774(3) Å respectively, and help stabilize the crystal structure. The conformations and intersections of five member rings will be presented.