Crystal structure of {[2-(diphenylphosphino)ethyl]diphenylphosphine oxide}iodonitrosylcobalt(0)

Abstract

Crystals of the title compound are monoclinic with a= 29·139(15), b= 9·002(5), c= 24·096(13)Å, β = 117·67(2)ο, Z= 8, space group C2/c. 1499 Counter intensities were used, and the structure was solved by Patterson and Fourier methods and refined by least squares to R 7·43%. Both nitrosyl groups are disordered between two alternative positions (A) and (B), but it was not possible to resolve the nitrogen atoms into N(A) and N(B). The co-ordination around the cobalt is distorted tetrahedral with N(1)-Co-N(2) 119·9°. Angles at the nitrogen atoms are: Co-N(1)-O(1A) 120·5, Co-N(1)-O(1B) 166·3, Co-N(2)-O(2A) 154·6, and Co-N(2)-O(2B) 149·0°. This is the first example of a distinctly bent M-N-O linkage in a four-co-ordinate nitrosyl complex. The mode of bonding of the nitrosyl ligands and their influence on the geometry of the complex are discussed.