title: Stabilization of a diphosphagermylene through pπ-pπ interactions with a trigonal-planar phosphorus center.
abstract: N-Heterocyclic carbenes and their heavier homologues are, in part, stabilized by delocalization of the N lone pairs into the vacant p-orbital at carbon (or a heavier Group 14 element center). These interactions are usually absent in the corresponding P-substituted species, owing to the large barrier to planarization of phosphorus. However, judicious selection of the substituents at phosphorus has enabled the synthesis of a diphosphagermylene, [(Dipp)2P]2 Ge, in which one of the P centers is planar (Dipp=2,6-diisopropylphenyl). The planar nature of this P center and the correspondingly short P-Ge distance suggest a significant degree of P-Ge multiple bond character that is due to delocalization of the phosphorus lone pair into the vacant p-orbital at germanium. DFT calculations support this proposition and NBO and AIM analyses are consistent with a Ge-P bond order greater than unity.
authors.affiliation: Main Group Chemistry Laboratories, School of Chemistry, Newcastle University, Bedson Building, Newcastle upon Tyne, NE1 7RU (UK) http://www.ncl.ac.uk/chemistry/staff/profile/keith.izod. keith.izod@ncl.ac.uk.
authors.forename: Keith
authors.initials: K
authors.lastname: Izod
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Rayner
authors.forename: Salima M
authors.initials: SM
authors.lastname: El-Hamruni
authors.forename: Ross W
authors.initials: RW
authors.lastname: Harrington
authors.forename: Ulrich
authors.initials: U
authors.lastname: Baisch
mesh_terms: D005857:Germanium / Q000737:chemistry*; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D010758:Phosphorus / Q000737:chemistry*
chemical_list: D008024:Ligands; D005857:Germanium; D010758:Phosphorus
keywords: NMR spectroscopy; P ligands; density functional calculations; germanium; solid-state structure