Polyfluoroalkylation

The esters of monochloro- and dichlorophosphoric acids having polyfluoroalkyl groups Rf, eg, Rf = (CF2)2CH2C—, CF2(CH2)2C—, CF2CH2—,... 

CH2(CF2CH2 2,4, been synthesized by the reaction of PCl and the lithium salt of the respective polyfluoroalkyl alcohols followed by... 

Pyrimidine, 2-phenyl-1,4,5,6-tetrahydro-synthesis, 3, 115 Pyrimidine, 2-phenylthio-synthesis, 3, 136 Pyrimidine, polychloro-as pharmaceuticals, 1, 157 Pyrimidine, polyfluoroalkyl-synthesis, 3, 77 Pyrimidine, 5-(2-pyrrolyl)-synthesis, 4, 228 Pyrimidine, styryl-oxidation, 3, 76 polymers, 1, 289 synthesis, 3, 76... 

Polyfluoroalkyl hypochlorites add to tetrafluoroethylene at room temperature [58] (equation 41)... 

Replacement of a hydrogen with bromine in the polyfluoroalkyl group of a ketone or acyl fluoride can be carried out with phosphorus pentabromide [i50] (equation 45)... 

Hydrolysis of geminal fluorides requires activation by per- or polyfluoroalkyl or perfluoroaryl groups and by double bonds linked to the same or adjacent carbon The activation is the result of reducing the electron density at the fluorinated carbon, facilitating attack by, primarily, nucleophilic reagents... 

Methyl 2-methoxy-2-polyfluoroalkyl-2-fluoroacetates, generated from poly-fluoroalkyltrifluoroethylene oxides and methanol, give, on heating with concentrated or fuming sulfuric acid, methyl polyfluoroalkylglyoxylates [29] (equation 32). 

Polyfluoroalkyl fluorosulfates react with substituted hydrazines to give the corresponding polyfluorocarboxylic hydrazides [90] (equation 78)... 

Sulfonates react with a variety of nucleophiles. Synthesis of M A -bis(trifluoro-methyl)aminotnfluoromethanesulfonate and its reactions with nucleophiles were investigated [33] (equation 31) (Table 13). Nucleophilic attack occurs at either nitrogen or sulfur amines give complex mixtures [33]. Polyfluoroalkyl fluorosul-fates react with amines, alcohols, or alkoxides to yield polyfluoroalkyl sulfamates and dialkyl sulfates, respectively [34] (equation 32) (Table 13). In these reactions. 

Addition Reactions across Polyfluoroalkyl- and Perfluoro-aUcyl-Substituted CO and CN Multiple Bond Systems... 

Polyfluoroalkyl- andperfluoroalkyl-substituted CO and CN multiple bonds as dipolarophiles. Dmzo alkanes are well known to react with carbonyl compounds, usually under very mild conditions, to give oxiranes and ketones The reaction has been interpreted as a nucleophilic attack of the diazo alkane on the carbonyl group to yield diazonium betaines or 1,2,3 oxadiazol 2 ines as reaction intermediates, which generally are too unstable to be isolated Aromatic diazo compounds react readily with partially fluorinated and perfluorinated ketones to give l,3,4-oxadiazol-3-ines m high yield At 25 °C and above, the aryloxa-diazolines lose nitrogen to give epoxides [111]... 

Polyfluoroalkyl- and Perfluoroalkyl-Substituted CO and CN Multiple Bonds as Dienophiles in [4+2] Cycloaddition Reactions... 

This discussion is separated into three sections depending on whether fluorine, or polyfluoroalkyl group, is introduced into a heterocycle or whether the heterocycle is formed from fluorinated synthons. Methods of introduction of fluorine into N-containing heterocyclic compounds have been reviewed (90CLY959). 

By far the most important polyfluoroalkyl group is the trifluoromethyl and a review of trifluoromethylation and related reactions has appeared (91BGJ2255). 

Aminopyridines can be perfluoroalkylated in a photoinduced electron transfer process. A charge transfer complex between the heterocycle and polyfluoroalkyl iodide, observable by NMR, is photolytically stimulated... 

Fluoride ion-catalyzed polyfluoroalkylation is a powerful method for introducing RF groups into polyfluoroazaaromatics. Trichloro-1,2,3-triazine is such a reactive system that fluorination and polyfluoroalkylation... 

Lewis acid catalysis has been used to promote stepwise [2 + 2] cycloaddition of silyl enol ethers and unsaturated esters.178 The best catalyst is (C2H5)2A1C1 and polyfluoroalkyl esters give the highest stereoselectivity. The reactions give the more stable trans products. 

Perfluoroalkyl iodides RfI and polyfluoroalkyl iodides of the type of RfCH2CH2I are directly oxidizable. Their oxidation potentials are summarized in Table 3 [35],... 

Polyfluoroalkyl Derivatives of Metalloids and Nonmetals R. E. Banks and R. N. Haszeldine... 

The per(poly)fluoroalkylation of olefins by per(poly)fluoroalkyl chlorides, initiated by ammonium peroxydisulfate and sodium formate, is also reported. The reaction proceeds smoothly in polar aprotic solvents. The presence of functional groups like sodium car-boxylate or sulfonate in the polyfluoroalkyl chloride appears to facilitate the reaction. This reaction represents the first example of the reactivity of per(poly)fluoroalkyl chlorides. 

Yamanaka and co-workers (74) effected the 1,3-dipolar cycloaddition between miinchnones 134 and polyfluoro-2-alkynoic acid esters to afford the corresponding 4-(polyfluoroalkyl)pyrrole-3-carboxylates (135). The reaction proceeds rapidly at low temperature and the various miinchnones (134) were generated from 1,3-oxazolium perchlorates 133 using the method of Boyd and Wright (6,7). Under... 

When R = N02 [108-110a] or SCI [109], the tetraalkyl orthocarbonates are obtained. When R = halogen, mainly orthoformates are formed except for the recent case describing the reaction of polyfluoroalkanols with carbon tetrachloride catalyzed by ferric chloride to give polyfluoroalkyl orthocarbonates [110b] (Eq. 26). 

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