Organometallics trifluoromethyl

Similarly, 1-alkylpyrroles, indoles, furans, thiophenes [60], a-picoline [61], enols, malonates [76], and organometallic compounds [56, 62] react with acyl imines of trifluoropyruvates to give derivatives of a-trifluoromethyl a-amino acids... 

As most readers will undoubtedly be aware, the study of trifluoro-methyl organometallic compounds, and the initiation of this area as a field of research, began with the discovery of bis(trifluoromethyl)mer-cury by Emele us and Haszeldine (1) in 1949 and continued with their associated research programs. Since that time, a steady, and sometimes spectacular, international research effort has continued over the past twenty-five years that has involved many laboratories (2). 

IV. Synthesis of Trifluoromethyl Organometallic Compounds by Direct Fluorination... 

A quite surprising development, even to experienced workers in elemental-fluorine chemistry, has been the synthesis of trifluoromethyl organometallic compounds by direct fluorination of metal alkyls (25). Even more surprising is the fact that, for certain metal and metalloid systems, such as the reaction of elemental fluorine with tetramethyl-germane, this t5rpe of low-temperature synthesis is a practical method 26) for the laboratory preparation of the perfluoro analog. 

V. A New General Synthesis for Trifluoromethyl Organometallic Compounds and Other Sigma-Bonded Metal Compounds Based on Metal Vapor as a Reagent... 

Using this technique, it is extremely easy to prepare almost all of the trifluoromethyl organometallic compounds that have been discussed... 

There is little difference between the chemical shifts of mono- and bis-trifluoromethyl organometallics, such as CF3-Zn-X and (CF3)2Zn, which absorb at -44.5 and -43.4ppm, respectively. 

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. 

Keywords Cation-radical salts, Molecular conductors, Organic superconductors, Organometallic anions, Tetrakis(trifluoromethyl)metallates, Tetrathiafulvalene... 

The reactions appear to be similar to organometallic synthesis, where the reduction is performed by the metal instead of electricity. However, these reactions have been shown to be essentially different from the corresponding organometallic reactions. This method has valuable advantages. As the anode reaction is controlled, an undivided cell can be used, the reaction occurs in one-step, the conditions are quite simple, and so on. Sibille and Perichon et al. have found that the sacrificial zinc anode is quite effective for trifluoromethylation of aldehydes to form trifluoromethylated alcohols in almost quantitative yields (Eq. 6) [19]. The reaction proceeds via the reduction of Zinc(II) salts, followed by a chemical reaction between the reduced metal, CF3Br, and aldehyde. 

The cell is suitable for the manufacture of (i) metal alkoxides, (ii) thiolates, (iii) carboxylates, (iv) hydroxides, (v) organometallics and chemicals such as diphenylacetic acid, (vi) ortho- and para-trifluoromethyl-benzoic acid, (vii) aryl-... 

---