Crystal and molecular structure of tris(3,3,4,4-tetramethyl- 3,4-dihydrodiazete)bis(tricarbonylchromium), (N2C2Me4)3[Cr(CO)3]2

Crystals of C₂₄H₃₆N₆O₆Cr₂ are monoclinic, a 15.380(3), b 13.965(2), c 14.459(3) Å, β 92.18(1)°; Z = 4; space group P2₁ with two independent molecules in the asymmetric unit. The crystal structure was determined from X-ray diffractometer data by direct methods and refined by least-squares methods to R = 0.066 for 2430 independent observed reflections. It consists of discrete molecules, in which each Cr atom is surrounded by three cis carbonyl groups and three cis nitrogen atoms of three 3,3,4,4-tetramethyl-1,2-diazetine ligands, in a deformed octahedral coordination. There is no evidence of intramolecular Cr ? Cr interaction.