Trifluoromethyl group anion

Hydrolysis of the trifluoromethyl group of 2 tnfluoiomethylimidazoles is promoted by the formation of the anion, which readily eliminates fluoride. The resultant ditluorodiazafulvene then easily adds water The remaining steps in the hydrolysis ate predictable When aqueous ammonia is used, 2-cyanoimidazoles result [40] (equation 4])... 

An amino group placed P (i.e., vicinal) to a trifluoromethyl group gives rise to considerable shielding, as can be seen from the examples given in Scheme 5.16. The hydrochloride salts are deshielded relative to the free base. In contrast, when it is placed vicinal to a tetrazolyl anion, the fluorines are deshielded. 

Stable organosilver(m) complexes having a general formula [Ag(GF3) X(4 )] with organic groups such as cyano, halo, methyl, alkynyl, difluoromethyl, and perfluoroethyl, replacing the trifluoromethyl groups in the [Ag(CF3)4] anion, as well as [Ag(CF3)3(NCMe)], were prepared. For instance, the air and moisture sensitive silver(i)... 

Fluorinated hydrocarbons are known to interact strongly even with rather hydrophilic anions. By introducing trifluoromethyl groups into the polymers you mentioned, I would expect a substantial increase in the binding of anions. Did you observe such an effect when introducing the trifluoromethyl labels ... 

Dixon and Smart71 examined a series of fluorine-substituted phosphonium ylides. Fluorine stabilizes carbanions via an inductive effect, favouring pyramidal carbanions. Dixon and Smart argued that the first substitution of F on the ylidic carbon (H3P=CHF) causes the carbon to become very pyramidal (the sum of the angles at C is 338.5°), which reduces the potential overlap of the anionic orbital with any P orbitals. The leads to the long P—C distance of 1.723 A. The second F substitution (H3P=CF2) actually breaks the P—C bond and the system is best described as a weak interaction of phosphine with CF2. Trifluoromethyl groups act to stabilize the anions via hyperconjugation. This leads to a planar ylidic carbon in H3P=C(CF3)2. 

Because of the electron withdrawal of the trifluoromethyl group, the a,P-double bond is polarized so that the a-carbon with respect to the trifluoromethyl group has a negative charge, and the P-carbon a positive charge. The p-carbon is thus fit to accept a nucleophile, water, whose hydroxyl is a better nucleophile than are the bromide or acetate anion. Redistribution of the double bonds gives the enol form of the product, l-(o-hydroxyphenyl)-2,3,3,3-tetrafluoro-l-propanone [<55]. 

In mixed trifluoroacetic anhydrides, the strong electron-withdrawing tri-fluoroacetyl group polarizes the bonds to the anhydride oxygen in such a way that it tends to split to acylium cation and trifluoroacetate anion [/0/. Generally, the products of the reaction of hydroxy compounds with acyl trifluoroacetates are esters of carboxylic acids and trifluoroacetic acid, because the acyl carbonyl is better fit for a nucleophilic attack than the carbonyl next to the trifluoromethyl group [707]. 

Despite the mature nature of this field [22], Huang and Caulton [70] have also discovered some unusual chemistry of the trifluoromethyl group bound to a co-ordinatively unsaturated Ru(II) phosphine complex. As shown below, treatment of RuHF(CO)L2 (L=PlBu2Me) with the trifluormethyl anion source Me3SiCF3/ CsF affords a difluorocarbene complex by a-fluoro migration. 

Treatment of trifluoromethyl(trimethyl)silane with fhe fused salt gives the tri-fluoromefhyl anion-equivalent species. This adds to the aldehyde in good yield to form fhe alcohol wifh a trifluoromethyl group (Scheme 2.11). 

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