Silver benzoate, reaction with

C. Pedersen and H. G. Fletcher Jr., Reaction of ethyl 5-O-benzoyl-l-thio-P-L-arabinoside with silver benzoate and with mercuric acetate, J. Org. Chem., 26 (1961) 1255-1257. 

Sodium thenoate is bromodecarboxylated in low yield, slower than sodium anisate, but more rapidly than sodium benzoate. However, the Hunsdiecker reaction with silver salts has been used preparatively for the synthesis of 2,3-dibromo-4-nitrothiophene from 3-bromo-4-nitro-2-thiophenecarboxylic acid. ... 

Suitable substrates for the Hunsdiecker reaction are first of all aliphatic carboxylates. Aromatic carboxylates do not react uniformly. Silver benzoates with electron-withdrawing substituents react to the corresponding bromobenzenes, while electron-donating substituents can give rise to formation of products where an aromatic hydrogen is replaced by bromine. For example the silver /)-methoxybenzoate 6 is converted to 3-bromo-4-methoxybenzoic acid 7 in good yield ... 

The equivalence of sulfur and oxygen in this ring system carries over to NSAIDs as well. Preparation of the sulfur analogue of isoxepac (6-4) starts with the alkylation of thiophenol (27-1) with benzyl chloride (26-1). Cyclization of the intermediate thioether (27-2) then affords the homothioxanthone (27-3). The carboxyl side chain is then extended by means of the Amdt-Eistert homologation reaction. The acid is thus hrst converted to its acid chloride by means of thionyl chloride. Reaction with excess diazomethane leads to the diazoketone (27-4). Treatment of that intermediate with silver benzoate and triethylamine leads the ketone to rearrange to an acetic acid. There is thus obtained tiopinac (27-5) [28]. 

The same result can be achieved in one step with m-chloroperoxybenzoic acid and water.719 Overall anti addition can also be achieved by the method of Prevost. In this method the olefin is treated with iodine and silver benzoate in a 1 2 molar ratio. The initial addition is anti and results in a 3-halo benzoate (71). These can be isolated, and this represents a method of addition of IOCOPh. However, under the normal reaction conditions, the iodine is replaced by a second PhCOO group. This is a nucleophilic substitution reaction, and it operates by the neighboring-group mechanism (p. 308), so the groups are still anti ... 

The syn- and anfi-diol epoxides of benz[a] anthracene and benzo[a] pyrene have been prepared from dihydroarenes by sequential Prevost reaction with silver benzoate-iodine, dehydrogenation, methanolysis, and epoxidation, e.g.,... 

The reaction of diazoketone 621 with either silver benzoate in methanol or with rhodium acetate in dichloromethane led to the formation of the stable azetinium salt 622, which was isolated as yellow crystals (Equation 236) <1998AGE2229>. 

The silver benzoate was made by reaction of silver nitrate with sodium benzoate in water. The submitters dried the silver benzoate and recrystallized it from N-methylpyrrolidone or dimothylforinamide. The checkers dried it in an oven at 130° for I hour immediately before use, but did not recrystallize it. Any precipitate present after dissolving the silver benzoate in I riot hylamine is removed by lilt rat ion or centrifugal ion. 

Anti hydroxylation of an alkene is readily achieved with peroxycarboxylic adds. Add-catalyzed ring opening of the irutial produd, an oxirane (epoxide), forms the monoester of a 1,2-diol, hydrolysis of which affords the parent diol. Alternative reagents whi ate often used for anti hydroxylation of alkenes are hydrogen peroxide with oxides of tungsten > 4.2i gj. selenium, 444i and iodine-silver benzoate (Pr6vost reaction).. ... 

Silver-mediated C—X bond formation was known for many years as the Hunsdiecker reaction, in which substrates bearing carboxylic acids are oxidatively decarboxylated to give alkyl halides in the presence of halogens (142). If olefins are used with silver benzoate and I2, the Prevost reaction occurs to yield diols (143). 

Provost reaction. This reaction constitutes an important step in a synthesis of frans-7,8-dihydroxy-anfi-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (3), considered to be the ultimate carcinogenic metabolite of benzo[a]pyrene. To obtain satisfactory yields, the silver benzoate should be freshly prepared (method of Newman and Beal, 1, 1004), and the biphase reaction should be stirred efficiently (Vibromixer with a large stirring blade). ... 

A similar conversion of olefins to glycols involves reaction with iodine and silver benzoate followed by saponification of the resulting crude di-... 

Mixed anhydrides (234 equation 126) are formed in the reaction of silver benzoate with imidoyl chlorides. Imidoyl chlorides react with alcohols or phenols in the presence of base (alkoxide, tertiary amine) to give imidates, e.g. (235 equation This method is especisdly useful for the... 

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