Trifluoroacetate compounds Metals, trifluoroacetates

Other Cesium Compounds. Cesium acetate [3396-11-0], CsOOCCH, mol wt 191.95, theoretical cesium content 69.24 wt % cesium trifluoroacetate, CF COOCs, mol wt 245.93, theoretical cesium content 54.04 wt % cesium—precious metal compounds such as cesium dicarbonyltetrachloromthenium, [22594-81-6] Cs2RuCl4(CO)2, mol wt 564.71, mthenium content of 17.9 wt %, a yellow crystalline powder and cesium tetrachlorogold [13682-60-5], CsAuCl, mol wt 471.7, gold content of 41.8 wt % a yellow powder are all known. 

Fluorinated olefins, such as chlorotritluoroethylene, hexafluoropropene, per-fluoroisobutylene, and hexafluorocyclobutene, react with silver trifluoroacetate in the presence of alkali metal fluondes to give perfluoroalkylsilver compounds [270] (equation 186)... 

Thallium(III), particularly as the trifluoroacetate salt, is also a reactive electrophilic metallating species, and a variety of synthetic schemes based on arylthallium intermediates have been devised.75 Arylthallium compounds are converted to chlorides or bromides by reaction with the appropriate cupric halide.76 Reaction with potassium iodide gives aryl iodides.77 Fluorides are prepared by successive treatment with potassium fluoride and boron trifluoride.78 Procedures for converting arylthallium compounds to nitriles and phenols have also been described.79... 

Attempted syntheses of trifluoromethyl derivatives of germanium, tin, and lead by thermal decarboxylation either resulted in decomposition of the trifluoroacetate without forming carbon dioxide (22,39,40) or gave carbon dioxide but no trifluoromethyl organometallic (22). In the latter case, the metal fluoride was detected. This suggests that the trifluoromethyl compound is thermally unstable and decomposes by fluoride abstraction. 

The imine 217, formed from acetophenone and the 1-aminoimidazole, has been transformed into the enamine 218 which is then cyclized to 219 in trifluoroacetic acid (TFA) (Equation 40) <1995SC3271 >. The diaminoimidazole 220 reacts with ynone 221 to form 222 (Equation 41) <1998CHE1189>. Bromochalcones and chalcone dibromides can also be used in place of the ynone. Similar reactions have been used to prepare the dihydro analogues of 222 <1999CHE1207>. The reaction between 1-aminoimidazoles and 1,3-diketones has been extended to prepare bis-heterocyclic compounds, for example, 223 as ligands for transition metals (Equation 42) <2005EJI4382>. 

Abstract Magnesium porphyrazines substituted with eight (phenyl-propene) groups on the peripheral positions have been prepared by cyclotetramerization of l,2-bis(3-phenyl-2-propenethio) maleonitrile and then achieved porphyrazine by 3-bromo-l-phenyl-l-propene. Metal-free derivative was obtained by its treatment with trifluoroacetic acid. The new compounds have been characterized by FT-IR, H-NMR, UV-VIS and elemental analysis methods. 

A number of reagents derived from nitrate salts and acid anhydrides have been reported for the V-nitration of amides and related compounds. Crivello first reported the use of metal nitrates in trifluoroacetic anhydride (TFAA) for the nitration of aromatic systems. Chapman... 

Metal-containing compounds, Rhodium Compounds (Continued) Hydridotetrakis(triphenylphosphine)-rhodium(I), 144 Rhodium(II) acetate, 226, 266 Rhodium(II) carboxylates, 226, 266 Rhodium(II) trifluoroacetate, 266 Tetra-jx3-carbonyldodecacarbonylhexa-rhodium, 152, 288... 

Thallation of aromatic compounds with thallium tris(trifluoroacetate) proceeds more readily than mer-curation and in many instances more selectively. Ortho derivatives are obtained frequendy when functional groups with unshared electron pairs are present to direct the metallation.39... 

As is general for organosilver compounds, perfluorophenylsilver is considerably more stable than phenylsilver.55 The first example of a perfluoroarylsilver compound was reported by Miller and Sun in 1970.49 Reaction of perfluorophenyllithium with silver trifluoroacetate, or of perfluorophenyl bromide with perfluoroisopropylsilver, gave perfluorophenylsilver as colorless crystals (Scheme 1.17). The compound was found to be stable up to 150°C, at which temperature it slowly dimerized to give perfluorobiphenyl and metallic silver. Since this initial report a number of syntheses of perfluorophenylsilver from perfluorophenyllithium followed.56,57... 

The second mechanism which cannot always be strictly differentiated from the first one 41) should be considered as a typical electrophilic substitution of the arene by the iiigh valent metal compound. The latter is still more electrophilic with tri-fluoroacetate than with acetate anions. The organometallic arene intermediates were isolable in some cases 43). In the second step, the metallic residue is substituted by the acetate or trifluoroacetate ion. 

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