BICYCLO PENTANE-1,3-DICARBOXYLIC ACID

Synonims 1,2-cyclohexanedicarboxylic, acid calcium salt octacosanoic acid, calcium salt (2 1) calcium difluoride propanedioic acid, calcium salt (1 1) 1,5-pentane dicarboxylic acid, calcium salt (lR,2R,3S,4S)-rel-bicyclo[2.2.1]heptane-2,3-dicarboxylic acid, disodium salt mixture of polycarbonic acid salt and inorganic carbonate in a polymeric carrier, sodium 2,2 -methylene-bis-(4,6-di-tert-butylphenyl)phosphate bicyclic (2,2,1) heptane di-carboxylate 1,2-cyclohexanedicarboxylic acid, calcium salt -i- zinc stearate bicyclo[2.2.1]heptane-2,3-dicarbo lic acid, disodium salt, (IR, 2R, 3S, 4S)-rel-and a blend of amorphous silicon dioxide coated wilh 13-docosenamide in a 1 1 ratio proprietary zinc compound octacosanoic acid, calcium salt (2 1) benzoic acid, lithium salt zinc monoglycerolate sodium benzoate encapsulated sodium salts of carbonic and poly-carboxylic acids with styrene and SEES rubber carrier resins zinc,[l,2,3-propanetriolato(2-)-k01,k02]homopolymer, stereoisomer... 

In a modified procedure the free carboxylic acid is treated with a mixture of mercuric oxide and bromine in carbon tetrachloride the otherwise necessary purification of the silver salt is thereby avoided. This procedure has been used in the first synthesis of [1.1.1 ]propellane 10. Bicyclo[l.l.l]pentane-l,3-dicarboxylic acid 8 has been converted to the dibromide 9 by the modified Hunsdiecker reaction. Treatment of 9 with t-butyllithium then resulted in a debromination and formation of the central carbon-carbon bond thus generating the propellane 10." ... 

Photochemical Synthesis of Bicyclo[1.1.1]pentane-1,3-dicarboxylic Acid. 

PHOTOCHEMICAL SYNTHESIS OF BICYCLO[1.1.1)PENTANE-1,3-DICARBOXYLIC ACID... 

B. Bicyclo[1.1.1]pentane-1,3-dicarboxylic acid (3). A 1-L, three-necked, round-bottomed flask, equipped with a mechanical stirrer, addition funnel, and thermometer is charged with a solution of 43.3 g (1.08 mol) of sodium hydroxide in 315 mL of water and 25.5 mL (79.1 g, 0.495 mol) of bromine. The mixture is cooled to 0°C. A solution of the diketone (10 g, 0.066 mol) obtained in Part A in 36 mL of dioxane is added dropwise at such a rate that the temperature does not exceed 3°C (Note 7). After the addition is finished, the reaction mixture is stirred for 1 hr at 0°C, then overnight at room temperature. Sodium bisulfite (1.8 g) is added and the solution is extracted with chloroform (3 x 50 mL). Subsequently, 36 mL of coned hydrochloric acid is added to the aqueous layer. After the acidified solution is cooled to room temperature, the mixture is continuously extracted with diethyl ether for 50 hr (Note 8) in an extraction apparatus. Evaporation of ether from the extract yields 9.68 g (94.5% from diketone 2) of pure diacid 3, mp 302-305°C, with decomposition [lit.4 mp, 305°C (d)] (Note 9). 

The original preparation of [l.l.l]propellane (177) involved Hunsdiecker degradation of bicyclo[1.1.0]pentane-l,3-dicarboxylic acid (178) to the dibromide 179 and then treatment of 179 with an alkyllithium. Unfortunately, 178 was only accessible with difficultyand [l.l.l]propellane remained effectively unavailable until Szeimies and coworkers reported a remarkable two-step synthesis in 1985. The commercially... 

The reader is referred to the synthesis of trimethylacetic acid,74 2-naphthoic acid,75 3,3-dimethylacrylic acid,76 3,3-dimethylglutaric acid,77 3(3-acetoxy-5-androstene-17(3-carboxylic acid,78 ethyl pyrrole-2-carboxylate,79 and bicyclo[ 1,1.1 ]pentane-1,3-dicarboxylic acid80 published in Organic Syntheses. 

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