1.2- Cyclohexanediols

Construct a molecu lar model of as 1 2 cyclohexanediol What IS the orientation of the OH groups axial or equatonaP... 

MeC(OTMS)=CH2, coned. HCl orTMSCl, 10-30 min, 80-85% yield. This method is effective for the formation of cis- or rrani -acetonides of 1,2-cyclohexanediol. 

Construct a molecu-I lar model of c/s-1,2-cyclohexanediol. What is the orientation of the OH groups, axial or equatorial ... 

Dimethyl-1,3-dioxolane, 326 frans-1,2-Cyclohexanediol Ketal, 327 frans-4,6-Dimethyl-1,3-dioxane, 327... 

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). 

The preparation of Pans-1,2-cyclohexanediol by oxidation of cyclohexene with peroxyformic acid and subsequent hydrolysis of the diol monoformate has been described, and other methods for the preparation of both cis- and trans-l,2-cyclohexanediols were cited. Subsequently the trans diol has been prepared by oxidation of cyclohexene with various peroxy acids, with hydrogen peroxide and selenium dioxide, and with iodine and silver acetate by the Prevost reaction. Alternative methods for preparing the trans isomer are hydroboration of various enol derivatives of cyclohexanone and reduction of Pans-2-cyclohexen-l-ol epoxide with lithium aluminum hydride. cis-1,2-Cyclohexanediol has been prepared by cis hydroxylation of cyclohexene with various reagents or catalysts derived from osmium tetroxide, by solvolysis of Pans-2-halocyclohexanol esters in a manner similar to the Woodward-Prevost reaction, by reduction of cis-2-cyclohexen-l-ol epoxide with lithium aluminum hydride, and by oxymercuration of 2-cyclohexen-l-ol with mercury(II) trifluoro-acetate in the presence of ehloral and subsequent reduction. ... 

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)... 

Reaction of trans-1,2-cyclohexanediol with para-formaldehyde in the presence of Indion 130 as catalyst to yield the corresponding cyclic formal has been successfully carried out (Matkar and Sharma, 1995). A conversion of 52% was realized with 70% selectivity towards cyclohexanediol formal the other side products are rrans-hexahydrobenzo-l,3,5-trioxypin, di(tra i -2-hydroxycyclo-hexyloxy) methane. 

RuCl3-3H20 combined with P(C6H5), catalyzes a reaction of N-substituted anilines with 2,3-butanediol or 1,2-cyclohexanediol to give 2,3-dimethylindoles or 1,2,3,4-tetrahydrocarbazoles. 

Mishchenko, A. P., M. E. Sarylova, V. M. Gryaznov, V. S. Smirnov, N. R. Roshan, V. P. Polyakova and E. M. Savitskii. 1977. Hydrogen permeability and catalytic activity of membranes made of palladium-copper alloys in relation to the dehydrogenation of 1,2-cyclohexanediol. Izv. Akad. Nauk SSSR, Ser. Khim. 7 1620-1622. 

A suspension of thallium (III) nitrate in pentane at room temperature can react with alkenes to give vtc-dinitrate esters. Cyclohexene reacts with this reagent to give 1,2-cyclohexanediol dinitrate (85 %) (as a mixture of isomers) and 15 % cyclopentanecarboxaldehyde (hydride shift in the dethallation step). Some alkenes react extremely slowly with this reagent e.g. isomeric 5-decenes. 

C12H19NU4 l-(2-Oxocyclohexyl)-1,2-cyclohexanediol oxime Electiode sensor Co 52... 

For cyclic 1,2-diol-Cr(V) complexes, the multiplicity of the room-temperature CW-EPR signal depends upon the cyclic strain in the ligand.50 For these systems, the observed EPR hyperfrne pattern of the Cr(V)-diolate2 formed by reduction of Cr(VI) with GSH in the presence of c/.v-1.2-cyclohexanediol (6) or trans-1,2-cv c I oh e x an ed i ol... 

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