Evaluating stereoelectronic properties of bulky dialkylterphenyl phosphine ligands
The stereoelectronic properties of a series of sterically hindered phosphines containing a terphenyl substituent, PRAr’ (R = alkyl; Ar’ = CH-2,6-Ar), have been evaluated by various methods. Their σ-donating capacity has been assessed on the basis of the carbon monoxide stretching frequencies in benc...
| Authors: | , , , , , , , |
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| Format: | article |
| Status: | Versión aceptada para publicación |
| Publication Date: | 2019 |
| Country: | España |
| Institution: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repository: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/204270 |
| Online Access: | http://hdl.handle.net/10261/204270 |
| Access Level: | Open access |
| Keyword: | Bulky phosphine Ligand parameterization Tolman Selenides Buried volume Terphenyl |
| Summary: | The stereoelectronic properties of a series of sterically hindered phosphines containing a terphenyl substituent, PRAr’ (R = alkyl; Ar’ = CH-2,6-Ar), have been evaluated by various methods. Their σ-donating capacity has been assessed on the basis of the carbon monoxide stretching frequencies in benchmark iridium [IrCl(CO)(PRAr’)] and rhodium [Rh(acac)(CO)(PRAr’)] (acac = acetylacetonate) complexes, as well as by measuring P–Se scalar coupling constants (J) for the corresponding phosphine selenides (Se=PRAr’). In turn, the steric profile of terphenyl phosphines has been gauged by calculating Tolman Cone Angle (TCA), ligand shielding (G) and percent buried volume (%V) parameters. These calculations have been carried out from both X-ray diffraction and DFT-optimized structures. We have also examined several of the widely used biaryl phosphines for comparative purposes. |
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