Cyclohexanediols trans-1,2-, diacetate

A. trans-l,2-Cyclohexanediol. In a 100-ml., round-bottomed flask equipped with a reflux condenser protected with a drying tube are placed a magnetic stirring bar, 17.56 g. (0.0667 mole) of thallium (I) acetate (Note 1), and 40 ml. of dried acetic acid (Note 2). The mixture is stirred and heated at reflux for 1 hour. To the cooled mixture are added 2.84 g. (3.5 ml., 0.0346 mole) of cyclohexene (Note 3) and 8.46 g. (0.0333 mole) of iodine (Note 4). The resulting suspension is stirred and heated at reflux for 9 hours (Note 5), and then cooled to room temperature. The yellow precipitate of thallium(I) iodide is filtered and washed thoroughly with ethyl ether. The filtrates are comhined, the solvents are removed under reduced pressure with a rotary evaporator (Note 6), and the residual liquid is dissolved in dry ethyl ether. The turbid solution is dried with anhydrous potassium carbonate, and the solvent is again removed by rotary evaporation (Note 6), affording 5.4-6.3 g. of trans-1,2-cyclohexanediol diacetate as a mobile, brown liquid (Note 7). 

The diacetate is dissolved in 25 ml. of 95% ethanol, a solution of 2.9 g. (0.073 mole) of sodium hydroxide in 11ml. of water is added, and the resulting mixture is heated under reflux for 3 hours. The solution is concentrated by rotary evaporation under reduced pressure, and the remaining syrup is extracted with six 50-ml. portions of chloroform. The combined extracts are dried over anhydrous magnesium sulfate and evaporated, providing 3.1-3.3 g. of a pale brown crystalline solid that melts at 97-103°. Recrystallization from carbon tetrachloride gives 2.5-2.7 g. (65-70% based on iodine) of trans-1,2-cyclohexanediol, m.p. 103-104° (Note 8). 

Cyclohexanediol diacetate, trans- (8,9) (1759-71-3) Thallixim(I) ethoxide Ethyl alcohol, thallium (1+) salt (8) Ethanol, thallium (1 + ) salt (9) (20398-06-5)... 

Acetoxylation of olefins. The oxidation of olefins with selenium dioxide in acetic acid results in allylic oxidation (1, 994-996 2, 360-361) however, if the reaction is catalyzed by sulfuric acid, the main product results from acetoxylation. Thus oxidation of cyclohexene under these conditions (110°, autoclave) gives 1,2-cyclohexanediol diacetate as a mixture of cis- (55%) and trans- (45%) isomers in 32% yield. Similarly, oxidation of 1-hexene gives 1,2-hexanediol... 

The action of ammonia on trans,trans-2-nitro-1,3-cyclohexanediol diacetate (216) and on deoxynitroinositol pentaacetates (185) furnished vicinal 2-nitro-l,3-diamines which were isolated as di-N-acetyl derivatives in high yields.145,179,180 Two successive elimination-addition processes evidently take place in these systems, as depicted for the reaction145 216 — 217. In tetraacetoxy-l,4-dinotrocyclohexane (187), however, elimination of acetate and addition of ammonia were followed by aromatization to 2,5-dinitroaniline.180... 

Acetoxycyclohexyl tosylate reacts with acetate ion to form 1,2-cyclohexanediol diacetate. The reaction is stereospecific—that is, the stereoisomers obtained as products depend on the stereoisomer used as a reactant. Recall that because 2-acetoxycyclohexyl tosylate has two asymmetric centers, it has four stereoisomers—two are cis and two are trans. Explain the following observations ... 

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