Phenyltrichloromethylmercury

2-dime thoxyethane (monoglyme) was purchased from Matheson Coleman and Bell and purified by distillation from lithium aluminum hydride. The use of unpurified solvent had little effect on the yield of product. 

Sodium trichloroacetate may be purchased from the Dow Chemical Company (96.4% pure by Cl analysis) or prepared by neutralizing trichloroacetic acid (Matheson Coleman and Bell) with aqueous sodium hydroxide to the phenolphthalein end point. The product is dried under vacuum for 12 hours, sieved, then dried an additional 12 hours under vacuum, all at room temperature. The salt prepared by this method and used in this preparation was 98.5% pure, based on chlorine analysis, and can be stored indefinitely without decomposition. The submitter has obtained nearly identical yields of phenyltrichloromethyl-mercury from the commercial and from the prepared salts. 

If all the reactants are stirred for several minutes at room temperature, they dissolve to give a turbid solution. Stirring while heating then becomes unnecessary, except to promote more even heating, since the refluxing solvent and carbon dioxide evolution keep the precipitated sodium chloride in suspension. 

Purity of the product was ascertained by quantitative X-ray fluorescence analysis for chlorine and mercury, which showed satisfactory agreement with calculated values. Compounds containing both mercury and chlorine are difficult to analyze by classical wet analytical procedures. 

Yields as high as 77% have been obtained by this procedure. It is difficult to recover all the product from the mother liquor. The use of a 1 1 ratio of sodium trichloroacetate and phenyl-mercuric chloride gave yields of 39-45%, while a 1.25 1 ratio gave a 61% yield of product. 

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Sodium trichloroacetate, thermal decomposition in presence of phe-nylmercuric chloride to give phenyltrichloromethylmercury, 46,9 ... 

Phenylmercuric chloride, conversion to phenyltrichloromethylmercury by reaction with sodium tri-chloroacetate, 46, 98 2-Phenyl-2-oxazolin-5-one, 47, 101 2-Phenyl-5-oxazolone, 47,101... 

Studies by the submitters have indicated that the procedure reported here is the preferred method for the preparation of bicyclo[3.2.1]octan-3-one. It employs readily available, inexpensive reagents, and the overall yield is good. In addition, the method can be used for the synthesis of the difficultly accessible next higher homologues of bicyclo[2.2.2]oct-2-ene as well as for derivatives of norbornene. Bicyclo[3.2.2]nonan-3-one and l-methylbicyclo[3.2.1]octan-3-one have been prepared by a similar route6 in 60% and 47% yields, respectively (based on adduct). However, the preferred procedure for the formation of the dichlorocarbene adduct of bicyclo[2.2.2]oct-2-ene is that of Seyferth using phenyltrichloromethylmercury. Even in this case the overall yield is moderate (37%). 

Among the important reagents for which preparative procedures are given are 2,2 -bipyridine (by nickel directed and catalyzed dehydrogenation of pyridine p. 5), formamidine acetate (p. 39), phenyltrichloromethylmercury (p. 98), and trimethyl- and triethyloxonium fluoroborate (pp. 120, 113). The preparation of palladium catalyst ( Lindlar ) for the selective reduction of acetylenes is described (p. 89), as is the use of di-phenyliodonium-2-carboxylate, as a precursor of benzyne in the synthesis of 1,2,3,4-tetraphenylnaphthalene (p. 107). 

Phenyltrichloromethylmercury has also been prepared by the reaction of phenylmercuric bromide with sodium methoxide and ethyl trichloroacetate (62-71% yield) of phenylmercuric chloride with potassium <-butoxide and chloroform (52% yield) of phenylmagnesium bromide with trichloromethylmercuric bromide (24% yield) of trichloromethylmercuric bromide with diphenyldichlorotin (49%) and of trichloromethylmercuric bromide with phenylmagnesium bromide (no yield given). 

Phenyltrihalomethylmercurials, including the title compound, can be thermally decomposed in the presence of olefins to yield the corresponding dichlorocyclopropane derivatives. Olefins such as tetrachloroethylene and ethylene, which give exceptionally low yields of dichlorocyclopropanes when treated with other reagents for generating dichlorocarbene (iCCU), give reasonable yields of dichlorocyclopropanes when heated with phenyltrichloromethylmercurials. ... 

Phenyltrichloromethylmercury Arylcarboxylic acids by dienone-benzene rearrangement... 

Phenyltrichloromethylmercury has been found to be an ineffective carbene source for the cyclopropanation of a number of (CH)jo alkenes (snoutene, basketene, bullvalene, etc.) whereas the Makosza procedure works well. With the bicyclo-decatetraene (74) only the bis-adduct (76) was obtained (Scheme 11), and this contrasts sharply with the 1974 report of Schroder, where (75 X = Br) was obtained. However, the intervention of (75 X == Cl) is reasonably implicated in the formation of (76). 

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