24316-34-5Relevant academic research and scientific papers
Organocatalyzed Fluoride Metathesis
Mulryan, Daniel,White, Andrew J. P.,Crimmin, Mark R.
supporting information, p. 9351 - 9355 (2020/11/30)
A new organocatalyzed fluoride metathesis reaction between fluoroarenes and carbonyl derivatives is reported. The reaction exchanges fluoride (F-) and alternate nucleophiles (OAc-, OCO2R-, SR-, Cl-, CN-, NCS-). The approach provides a conceptually novel route to manipulate the fluorine content of organic molecules. When the fluorination and defluorination steps are combined into a single catalytic cycle, a byproduct free and 100% atom-efficient reaction can be achieved.
Reactions of 4-substituted tetrafluoropyridine derivatives with sulfur nucleophiles: SNAr and annelation processes
Fox, Mark A.,Sandford, Graham,Slater, Rachel,Yufit, Dmitrii S.,Howard, Judith A.K.,Vong, Antonio
, p. 148 - 154 (2012/11/13)
Reactions of model sulfur centred nucleophiles with 4-nitro-, 4-phenylsulfonyl- and 4-cyano-tetrafluoropyridine gave products arising from substitution of the nitro- and sulfonyl substituent or ring fluorine respectively. Ring fused products are formed up
Synthetic utility of 4-bromo-2,3,5,6-tetrafluoropyridine
Christopher, John A.,Brophy, Laura,Lynn, Sean M.,Miller, David D.,Sloan, Lisa A.,Sandford, Graham
, p. 447 - 454 (2008/12/21)
The regiochemistry of nucleophilic substitution of 4-bromo-2,3,5,6-tetrafluoropyridine has been investigated. Efficient, regioselective reactions occur with alkylamine, benzylamine and alkoxide nucleophiles, yielding products where substitution occurs ortho to the ring nitrogen. The resulting 2-substituted-4-bromo-3,5,6-trifluoropyridines can be functionalised further, either by a second regioselective nucleophilic displacement or palladium catalysed elaboration at the 4-position. Reactions with aromatic N-nucleophiles yield mixtures of ortho- and para-substituted products.
Trifluoromethanethiolate Ion. Part 2. Nucleophilic Substitution in Pentafluoropyridine. Synthesis and Characteristics of Trifluoromethylthio and Trifluoromethylsulphonyl Derivatives
Dmowski, Wojciech,Haas, Alois
, p. 2119 - 2124 (2007/10/02)
The CF3S(1-) anion, generated from thiocarbonyl difluoride or its trimer and caesium fluoride, reacted with pentafluoropyridine (1) at -15 deg C to give a high yield of 2,3,5,6-tetrafluoro-4-trifluoromethylthio-pyridine (2).When the trimer was used as a precursor of the CF3S(1-) anion, compound (2) reacted further at 20 deg C to give a mixture of mono- (2), bis- (3) and (4), and tris-(trifluoromethylthio) (5) substituted fluoropyridines.At 100-110 deg C, 2,4,6-trifluoro-3,5-bis(trifluoromethylthio)pyridine (4) was obtained as the only product.On oxidation with CrO3 in conc. sulphuric acid compound (2) gave 2,3,5,6-tetrafluoro-4-trifluoromethylsulphonylpyridine (12), and the oxidation of compound (4) led to a mixture of 2,4,6-trifluoro-3,5-bis(trifluoromethylsulphonyl)pyridine (13) and two isomeric fluoro-3,5-bis(trifluoromethylsulphonyl)pyridinediols (14a) and (14b).The sulphone (12) reacted readily with monomeric CF2S to yield a mixture of compounds (3), (5), and 2,4,5,6-tetrafluoro-3-trifluoromethylthiopyridine (15).The reaction of compound (2) with potassium thiophenolate and potassium phenolate also led to a substitution of fluorines and the CF3S group with the PhS or PhO substituents to give compounds (7)-(11).The sulphone (13) readily reacts with methanol to yield 2,4,6-trimethoxy-3,5-bis(trifluoromethylsulphonyl)pyridine (18).The structures of the new pyridine derivatives (2)-(5), (7)-(15), and (18) have been elucidated from the m.s., 19F n.m.r., and 13C n.m.r. spectra.The X-ray molecular sructure of derivative (18) has been obtained.
