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Hydrofluorination of Alkynes Catalysed by Gold Bifluorides.

ABSTRACT: We report the synthesis of nine new N-heterocyclic carbene gold bifluoride complexes starting from the corresponding N-heterocyclic carbene gold hydroxides. A new methodology to access N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) fluoride starting from N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) hydroxide and readily available potassium bifluoride is also reported. These gold bifluorides were shown to be efficient catalysts in the hydrofluorination of symmetrical and unsymmetrical alkynes, thus affording fluorinated stilbene analogues and fluorovinyl thioethers in good to excellent yields with high stereo- and regioselectivity. The method is exploited further to access a fluorinated combretastatin analogue selectively in two steps starting from commercially available reagents.

SUBMITTER: Nahra F

PROVIDER: S-EPMC4515107 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Hydrofluorination of Alkynes Catalysed by Gold Bifluorides.

Nahra Fady F Patrick Scott R SR Bello Davide D Brill Marcel M Obled Alan A Cordes David B DB Slawin Alexandra M Z AM O'Hagan David D Nolan Steven P SP

ChemCatChem 20141126 2

We report the synthesis of nine new N-heterocyclic carbene gold bifluoride complexes starting from the corresponding N-heterocyclic carbene gold hydroxides. A new methodology to access N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) fluoride starting from N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) hydroxide and readily available potassium bifluoride is also reported. These gold bifluorides were shown to be efficient catalysts in the hydrofluor ...[more]

PMID: 26236406

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