Trans-Cyclohexane-13-dicarboxylic acid

Crystalline polyesters from CHDM and aliphatic diacids are possible, but generally are of little interest because of low melting points and low glass-transition temperatures. Cyclic aliphatic diacids offer some potentially attractive possibilities since the melting points are not so depressed. For example, the polyester of CHDM with the high trans isomer of 1,4-cyclohexane dicarboxylic acid has a melting point similar to that of PBT (7). 

CgHi2O2 f 5,5-Dimethyl-1,3-cyclohexanedione, 40B, 143 C8H12O4, (+)-trans-1,2-Cyclohexane dicarboxylic acid, 34B, 90 C8H12O1, DL-trans-1, 2-Cyclohexane dicarboxylic acid, 34B, 9l C8Hi20fl, cis-1,2-Cyclohexanedicarboxylic acid, 35B, 106 C8Hi20fl, trans-Cyclohexane-1,4-dicarboxylic acid, 31B, 87 38B, 176 C H nO, 4,4-Dimethylcyclohexanone, 43B, 176... 

Octahydro- (we have used this nomenclature throughout) or perhydrobenzo[c]thiophene (35) exists as the cis and trans isomers and is more commonly named 2-thiahydrindane or 8-thiabicyclo-[4.3.0]nonane. Each stereoisomer may be prepared by treating the corresponding isomer of l,2-di(bromomethyl)cyclohexane with sodium sulfide (details of the products are given in Table IV).45 Cyclization of the cis isomer may be effected partially with thiourea via the formation of cis-hexahydro-o-xylylenebis(isothiouronium bromide) with sodium disulfide it gives a mixture of cis-octahydro-benzo[c]thiophene and cis-2,3-dithiadecalin.46 Optically pure ( —)-(8 R,9I )-lran -octahydrobenzo[c]thiophene has been prepared from (+ )-dicarboxylic acid via reduction of the diacid to the diol, tosylation, and ring closure of the bistosylate with sodium sulfide.47... 

Eastman Kodak (31) has developped a process in which dimethylterephthalate is first hydrogenated to a mixture of cis-and trans-cyclohexane-1, U-dicarboxylic acid dimethylester. 

C12H20O4 (+-)-trans-cyclohexane-l,2-dicarboxylic acid diethyl ester 96836-97-4... 

C12H20O4 trans-cyclohexane-1,4-dicarboxylic acid diethyl ester 19145-96-1... 

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