Bromidocarbonyl{(1S,2S)-N-[2-(dicyclohexylphosphanyl)ethylidenyl]-N′-[2-(diphenylphosphanyl)ethyl]-1,2-diphenylethane-1,2-diamine}iron(II) tetraphenylborate

Abstract

In the title compound, trans-(S,S)-[FeBr(CO)(PPh2CH2CH2NHCHPhCHPhNCHCH2PCy2)]BPh4, the FeII ion is in a distorted octahedral complex geometry with a cis-β ligand geometry in which two diastereomers co-crystallized in the asymmetric unit. These diastereomers differ by the orientation of the N—H moieties on the ligand; one is in the S conformation (A), and the other R (B). Diasteromer A has a P—Fe—P angle of 104.36 (6)° and B has a P—Fe—P angle of 102.70 (6)°. During the refinement of the structure, electron density peaks were located that were believed to be highly disordered solvent molecules (possibly diethyl ether). Attempts made to model the solvent molecule were not successful. The SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] option in PLATON indicated there was a large solvent cavity of 363 Å3. In the final cycles of refinement, this contribution of 117 electrons to the electron density was removed from the observed data. The density, the F(000) value, the molecular weight and the formula are given without taking into account the results obtained with SQUEEZE.

Keywords

• crystal structure
• diastereomers
• cis-β ligand geometry