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Versatility and adaptative behaviour of the P^N chelating ligand MeDalphos within gold(i) π complexes† † Electronic supplementary information (ESI) available: Experimental and computational details, analytical data and NMR spectra. CCDC 1967901 (3), 1967904 (5), 1967902 (6), 1967903 (7), 1967905 (9) and 1967906 (13g). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c9sc06398f

ABSTRACT: The hemilabile P^N ligand MeDalphos enables access to a wide range of stable gold(i) π-complexes with unbiased alkenes and alkynes, as well as electron-rich alkenes and for the first time electron-poor ones. All complexes have been characterized by multi-nuclear NMR spectroscopy and whenever possible, by X-ray diffraction analyses. They all adopt a rare tricoordinate environment around gold(i), with chelation of the P^N ligand and side-on coordination of the alkene, including the electron-rich one, 3,4-dihydro-2H-pyrane. The strength of the N → Au coordination varies significantly in the series. It is the way the P^N ligand accommodates the electronic demand at gold, depending on the alkene. Comparatively, when the chelating P^P ligand (ortho-carboranyl)(PPh2)2 is used, gold(i) π-complexes are only isolable with unbiased alkenes. The bonding situation within the gold(i) P^N π-complexes has been thoroughly analyzed by DFT calculations supplemented by Charge Decomposition Analyses (CDA), Natural Bond Orbital (NBO) and Atoms-in-Molecules (AIM) analyses. Noticeable variations in the donation/back-donation ratio, C

SUBMITTER: Navarro M

PROVIDER: S-EPMC8157524 | biostudies-literature |

REPOSITORIES: biostudies-literature

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