The Crystal and Molecular-Structure of fac,fac-Mo₂(CO)₆(Ph₂AsCH₂CH₂PPh₂)₃ a Case of Chemically Imposed Disorder in the Crystal Structure

Abstract

Crystals of fac,fac-Mo₂(CO)₆(ape)₃ (ape = Ph₂AsCH₂CH₂PPh₂) are monoclinic, P 2₁/n (No. 14), a 15.842(4), b 17.178(4), c 14.144(4) Å, β 98.80(3)º. The compound is dimeric with a bridging ape group, and the stereochemical arrangement of the carbonyl groups about each metal atom is facial. The facial arrangement leads to a chemically imposed disorder among the ape ligand donor atoms; this makes it impossible to distinguish arsenic and phosphorus atoms in the crystal structure determination.