An Insight into the Structure of Model Germaphosphaallenes

Ioan Silaghi-Dumitrescu (1) , P. M. Petrar (2) , G. Nemes Nemes (2) , J. Escudiéb (3) , H. Ranaivonjatovob (3)

1 Department of Chemistry
2 UBB - Babes-Bolyai University [Cluj-Napoca]
3 LHFA - Laboratoire Hétérochimie Fondamentale et Appliquée

The geometries of all possible isomers of the model compound H2Ge=C=PH were optimized at the B3LYP/6-31G(d,p) level of the theory. The calculation were repeated at higher correlated methods with similar results and for the isomers of the methyl-substituted phosphagermaallene MeP=C=GeMe2. As another way to stabilise the P=C=Ge unit consists in the use electronic effects, a NBO study was carried out in order to identify the influence that the nature of several substituents would have on the strength of the C=Ge bond. Model compounds HP=C=GeR2 and HP=C=GeRR' were investigated (R = BH2, CH3, SiH3, NH2, OMe, F; R' = H). It was found that the main interaction contributing to the weakening of the C=Ge bond is a transfer of electron density from the lone pair of the phosphorus atom to the molecular antibonding orbital localized on the Ge-C bond.

Mots clés: Physical Sciences

Ioan Silaghi-Dumitrescu, P. M. Petrar, G. Nemes Nemes, J. Escudiéb, H. Ranaivonjatovob. An Insight into the Structure of Model Germaphosphaallenes. Molecular Physics, 2009, 107 (08-12), pp.1161-1167. ⟨10.1080/00268970902780288⟩. ⟨hal-00513258⟩