13344-76-8Relevant articles and documents
Access to novel fluorovinylidene ligands via exploitation of outer-sphere electrophilic fluorination: New insights into C-F bond formation and activation
Milner, Lucy M.,Hall, Lewis M.,Pridmore, Natalie E.,Skeats, Matthew K.,Whitwood, Adrian C.,Lynam, Jason M.,Slattery, John M.
, p. 1717 - 1726 (2016)
Metal vinylidene complexes are widely encountered, or postulated, as intermediates in a range of important metal-mediated transformations of alkynes. However, fluorovinylidene complexes have rarely been described and their reactivity is largely unexplored. By making use of the novel outer-sphere electrophilic fluorination (OSEF) strategy we have developed a rapid, robust and convenient method for the preparation of fluorovinylidene and trifluoromethylvinylidene ruthenium complexes from non-fluorinated alkynes. Spectroscopic investigations (NMR and UV/Vis), coupled with TD-DFT studies, show that fluorine incorporation results in significant changes to the electronic structure of the vinylidene ligand. The reactivity of fluorovinylidene complexes shows many similarities to non-fluorinated analogues, but also some interesting differences, including a propensity to undergo unexpected C-F bond cleavage reactions. Heating fluorovinylidene complex [Ru(η5-C5H5)(PPh3)2(CC{F}R)][BF4] led to C-H activation of a PPh3 ligand to form an orthometallated fluorovinylphosphonium ligand. Reaction with pyridine led to nucleophilic attack at the metal-bound carbon atom of the vinylidene to form a vinyl pyridinium species, which undergoes both C-H and C-F activation to give a novel pyridylidene complex. Addition of water, in the presence of chloride, leads to anti-Markovnikov hydration of a fluorovinylidene complex to form an α-fluoroaldehyde, which slowly rearranges to its acyl fluoride isomer. Therefore, fluorovinylidenes ligands may be viewed as synthetic equivalents of 1-fluoroalkynes providing access to reactivity not possible by other routes.
FORMATION OF BONDS BY OUTER-SPHERE OXIDATIVE ELECTROPHILIC FLUORINATION
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Page/Page column 66; 67, (2016/06/28)
There is described a method of fluorination of an alkenyl, alkynyl, aryl or isonitrile compound which comprises reacting an alkenyl, alkynyl, aryl or isonitrile compound with a metal-mediated outer-sphere electrophilic fluorinating (OSEF) agent.
Synthesis of γ-Fluoro-α,β-unsaturated Carboxylic Esters from Saturated α-Fluoro Aldehydes
Oldendorf, Jens,Haufe, Gu?nter
, p. 52 - 57 (2007/10/03)
γ-Fluoro-α,β-unsaturated carboxylic esters 7a, 7b and 7d and 4-fluoro-4-phenylbut-3-enoic ester (8) are obtained by two alternative pathways from 2-fluoro aldehydes 5a-d, either by Horner-Wadsworth-Emmons reaction or by Wittig reaction. The aldehydes 5a-d are prepared by Swern oxidation of the corresponding fluorohydrins 4a-d. These are available from α-olefins by bromofluorination, bromine-by-acetate replacement and subsequent hydrolysis.
