Conformational analysis of triphenylphosphine ligands in stereogenic monometallic complexes: tools for predicting the preferred configuration of the triphenylphosphine rotor.
Dalton Trans
; 44(12): 5451-66, 2015 Mar 28.
Article
em En
| MEDLINE
| ID: mdl-25692758
ABSTRACT
The extension of our simple model for predicting the propeller configuration of a triphenylphosphine ligand co-ordinated to achiral metal centres to include stereogenic metal systems is described. By considering nadir energy planes (NEP's) and a series of rigid-body calculations, a model has been developed to reliably predict the configuration of the triphenylphosphine rotor of stereogenic metal complexes. For complexes of the form [M(η(5)-C5H5)(PPh3)(L(1))(L(2))], where it is assumed that L(1) is larger than L(2), the configuration of the triphenylphosphine rotor may be predicted by viewing a Newman projection along the L(1)-M bond. In the orientation where the PPh3 unit is pointing vertically downwards and the orthogonal L(2) ligand is pointing to the right [i.e., an (RM)-configured complex, assuming that L(2) is ranked higher priority than L(1)], the conformation of L(1) can be expected to place the most sterically demanding substituent in the top-right quadrant. In cases where ligand L(1) still presents a steric incursion towards the PPh3 ligand (any part of L(1) other than H proximal to the PPh3 in the approximate zone -30° to +60° from the M-P bond) an (M)-configured rotor is expected, and when this interaction is not present a (P)-configured propeller is predicted. Without exception, these rules are consistent with all empirical data (>140 known crystal structures).
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01-internacional
Base de dados:
MEDLINE
Assunto principal:
Compostos Organofosforados
/
Complexos de Coordenação
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article