XL-Xantphos: Design and Synthesis of a Mechanistic Probe of Xantphos O-Coordination in Catalytic Reactions

Autor:	Gregory T. Whiteker, Robert D. J. Froese, Jerzy Klosin, Fangzheng Li, Amaruka Hazari, Michael L. Tulchinsky
Rok vydání:	2019
Předmět:	Xanthene Ligand Xantphos Organic Chemistry Regioselectivity Bite angle Medicinal chemistry Inorganic Chemistry chemistry.chemical_compound chemistry Physical and Theoretical Chemistry Cis–trans isomerism Phosphine Hydroformylation
Zdroj:	Organometallics. 38:2233-2238
ISSN:	1520-6041 0276-7333
DOI:	10.1021/acs.organomet.9b00141
Popis:	The synthesis and characterization of an analog of the Xantphos ligand that is geometrically incapable of coordination of the xanthene bridging oxygen atom is reported. This new ligand, XL-Xantphos, ((9,9-dimethyl-9H-xanthene-4,5-diyl)bis(4,1-phenylene))bis(diphenylphosphane), was studied in homogeneous, catalytic reactions for comparison with Xantphos. The XL-Xantphos ligand performed essentially identically to Xantphos in Rh-catalyzed hydroformylation of 1-octene, which suggests that the high regioselectivity for linear aldehyde is due to the large bite angle of these ligands and is not influenced by oxygen coordination to the metal. The Pd-catalyzed amidocarbonylation of 4-bromoanisole with dimethylhydroxylamine hydrochloride similarly showed no difference between Xantphos and XL-Xantphos. Computations on Pd(II) phosphine complexes at the DLPNO–CCSD(T) level of theory indicated that these ligands have different preferences for cis and trans coordination modes. The XL-Xantphos ligand has a thermodynamic...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::92095f7e6df500d792231bf4bfd8ec7c https://doi.org/10.1021/acs.organomet.9b00141 Zobrazit plný text záznamu