Mercuri-bis compounds, preparation

Bromomercuri-2 4-diphenyl-selenophene is prepared by the methods outlined above or by heating the mercuri-bis compound for ten minutes with mercuric bromide in acetone solution. It crystallises from alcohol in microscopic, colourless, felted hairs, M.pt. 215° C, (corr.), soluble in benzene, toluene, or glacial acetic acid. When its toluene solution is boiled, it decomposes with formation of diphenyl-selenophene and mercurous bromide. 

Substitutions in the CTR were studied in collaboration with Anisimov, Kolobova, Makarov, and Baryshnikov. We sulfonated (380) and mercurated (380) the compound, and metalated it (372) with butyllithium in THF. Lithiated CTR gave CTR-carboxylic acid (pK 4.73 in 50% aqueous ethanol at 25°C cf. pj of CTM-carboxylic acid, 4.99). CTR boric acid was also prepared (377) it hydrolyzed even more easily than its CTM analog. Mercury-bis-CTR produced chloro- or bromo-CTR on treatment with CuXj (377). 

The first trifiuorosilyl "organometallic compound, bis(trifiuorosi-lyl)mercury, has been prepared by using the new, metal-vapor technique (35). 

Acetoxymercuri-2 4-dichloroaniline 1 is prepared in the usual manner from 2 4-dichloroaniline and mercuric acetate in dilute alcoholic solution. It melts at 170° to 171° C., forms a hydroxide and chloride, M.pt. 280° C. and 198° C, respectively. The acetyl derivative, M.pt. 288° yields 2 4 6-trichloroacetanilide. In this case a mer-curi-bis compound is obtained by the action of sodium hydrogen sulphate on the acetate. It is Q-mercuri-his- 4<-dichloroaniUne, M.pt. 1GS° C. 

Mercuri-bis-o-anisole.—The best method of obtaining this compound is that due to Whitmore and Middleton, which consists of heating o-iodomercuri anisole with alcoholic potassium iodide solution in a reflux apparatus. It also occurs as a by-product in the preparation of o-iodomercurianisole, from which compound it may also be derived by the action of sodium stannite solution. 

The noble-gas compounds xenon bis(pentafluoro-orthoselenate) and xenon bis(pentafluoro-orthotellurate) are the most thermally stable of the Xe(OR)2 compounds so far known. The first decomposition products of these compounds have now been shown291 to be SeOFs and TeOF5, as shown by e.s.r spectra at low temperatures. U.v. irradiation of the xenon bis(fluoro-orthochalcogenates) at room temperature results in the quantitative formation of the peroxides F5MOOMF5 (M = Se or Te). Attempts to prepare the compound FOTeFs were unsuccesful, but the compound ClOTeFs was prepared by the reaction of mercury bis(pentafluoro-ortho-tellurate) with C1F. 

Pentafluorophenyllithium in ether reacts slowly with mercury at 15° C to afford bis(pentafluorophenyl)mercury, a compound recently prepared by another route (Section VII, B). The lithium reagent has very recently been used to prepare pentafluorophenyl derivatives of boron (79a), tin 19b), lead 19b), and several transition metals 19c). 

Ligand exchange reactions can be used to prepare perfluoroalkylzinc compounds Solvated trifluoromethylzinc compounds can be synthesized via the reaction of dialkylzincs with bis(trifluoromethyl)mercury [36] (equation 27) A similar exchange process with bis(trif]uorometliyl)cadinium and diraethylzinc gives a mixture of tnfluoromethylcadmium and zinc compounds [77]... 

The photochemical or thermal reaction between petfluoroalkyl iodides and mercury-cadmium amalgams has been used for the synthesis of perfluoro-alkylmercury compounds [150] Functionalized analogues have been prepared similarly via this route [151, 152] (equation 117), and the preparation of bis(tri-fluoromethyl)mercury has been described [153]... 

Previously, trifluorosilyl groups have been bound to phosphorus (40) and silicon via the SiF (g), fluorine-bond insertion-mechanism (41). The new compound HgCSiFs) is readily hydrolyzed, but it can be stored for long periods of time in an inert atmosphere. It is a volatile, white solid that is stable up to at least 80°C. The preparation of bis(trifluoro-silyDmercury, of course, raises the possibility of (a) synthesis of the complete series of trifluorosilyl, "silametallic compounds, as had previously been done for bis(trifluoromethyl)mercury by using conventional syntheses, and (b) transfer reactions similar to those in Section II, as well as (c) further exploration of the metal-vapor approach. The compound Hg(SiF.,)j appears also to be a convenient source of difluoro-silane upon thermal decomposition, analogous to bis(trifluoromethyl)-mercury ... 

Thiamin (vitamin B-l, 177) when photolysed, gives preparations having a characteristic odour. Photolysis of an aqueous solution with a high-pressure mercury lamp is reported to give the pyrimidine (178) [ 113]. Other work used irradiation at 254 nm and concentrated on the approximately 0.1% yield of ether-soluble odoriferous products. As many as nine compounds have been identified (179), (180), (181), 2-methyl-3-formyl-4,5-dihydrofuran, 3-acetyl-4,5-dihydrofuran, 4-oxopentyl formate, 3-formyl-5-hydroxypentan-2-one, 3-mercapto-2-methyl-4,5-dihydrofuran and bis(4,5-dihydro-2-methylfuran-3-yl)disulphide [114, 115]. 

The most extensively investigated 1,2-diazocines are 3,4,5,6,7,8-hexahydro derivatives, of interest in connection with studies on the properties of cyclic azo compounds. These compounds are obtained from the hydrazines (159) usually not isolated, by oxidation with yellow mercury(II) oxide. 3,8-Diaryloctahydrodiazocines are prepared by reduction of the azines dialkyl and unsubstituted derivatives are obtained by hydrolysis of the N,N-bis(ethoxycarbonyl) compounds (69JA3226,70JA4922). Cyclization of 2,7-diaminooctane with IFs gave the 3,3,8,8-tetramethyl compound (78CB596). 

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