Crystal structure of decacarbonyl-µ-[1,2-bis(dimethylarsino)tetrafluorocyclobutene-As,As]-triangulo-triruthenium [(Me2AsCC(AsMe2)CF2·CF2)Ru3(CO)10]

Abstract

Decacarbonyl-µ-[1,2-bis(dimethylarsino)tetrafluorocyclobutene-As, As]-triangulo-triuthenium, [(Me₂As[graphic omitted]F₂)Ru₃(CO)₁₀] crystallizes in the orthorhombic space group P2₁2₁2₁, a= 8·594, b= 18·795, c= 16·69 Å, Z= 4. The structure was solved by Patterson and Fourier methods applied to Mo-K_α diffractometer data, and was refined by least-squares procedures to a final R of 0·076 for 1828 observed (of a total of 2028) reflexions. The compound is a derivative of Ru₃(CO)₁₂ in which one equatorial carbonyl group on each of two ruthenium atoms is replaced by an arsenic atom of the diarsine ligand so that the plane of the diarsine ligand is twisted 18° with respect to the plane of the ruthenium triangle. Ru–Ru bond distances are 2·831, 2·831, and 2·858 Å the difference between the short and long bond lengths being significant in terms of the bonding characteristics of the ligand.