Cyclohexane, iodo

DIETHYL ESTER, 33, 23 Cycloheptanone, 34, 19, 24 sodium bisulfite adduct, 34, 25 Cyclohexane, iodo-, 31, 66 A1, -Cyclohexaneacetic acid, a-CYANO-, 31, 25, 26... 

It is believed that equatorial substituents such as chlorine or bromine would increase the guest diameter beyond the allowed values (assuming that the guest molecules stack roughly parallel to the canal68)). Support for this comes from the study of fluorocyclohexane where the population of the axial conformer is not enhanced to any major extent70. Nitro-71) and cyano-cyclohexane, trans-l,2-dichloro-, trans-1,2-dibromo-, tram-1,4-dichloro-, trans-1,4-dibromo-, and trans-l-bromo-4-chloro-cyclohexane all pack most efficiently in the thiourea canals as the axial or diaxial conformer 68,72. Tram-2,3-dichloro-1,4-dioxane behaves similarly73. In contrast isocyanato-, tram-1,4-diiodo-, trans-1 -bromo-4-iodo-, and tram-1 -chloro-4-iodo-cyclohexane are present as mixtures of the axial/equatorial or diaxial/diequatorial conformations as appropriate 68,72). The reason for this anomalous behaviour of the iodosubstituted cyclohexanes is not clear. 

B. 3 -Acetoxy-18-iodo- and 18-hydroxy-18,20 -oxido-5-pregnene. In a 5-1. three-necked flask fitted with a mechanical stirrer, a thermometer, and a reflux condenser are placed 31. of cyclohexane (Note 6), 180 g. ca. 0.37 mole) of commercial lead tetraacetate containing approximately 10% acetic acid (Note 7), 24 g. (0.095 mole) of iodine and 30 g. (0.083 mole) of 3j3-acetoxy-20j8-hydroxy-5-pregnene. The reaction mixture is stirred and heated to the boiling point by irradiation with a 1000-watt lamp (Note 8) from underneath. When the iodine color has disappeared (usually after about 60-90 minutes) (Note 9), the reaction mixture is cooled to room temperature, filtered with suction, and the... 

Treatment of owK-l-iodo-2-(pcrfluoropropyl (cyclohexane (trans-H 1) with sodium methoxide gives 3-(perfluoropropyl)cyclohexene (33) in a yield of 64% via anti elimination and l-(per-fluoropropyl)cyclohexene (32) in a yield of 13% via syn elimination of hydrogen iodide.77... 

Cyclohexanamine, N-[(2-bromo-4,5-dimethoxyphenyl)methylene]-, 65, 108 Cyclohexanamine, N-[(2-iodo-4,5-dimethoxyphenyl)methylene]-, 65, 108 CYCLOHEXANE, 1,2-BIS(METHYLENE)-, 65, 90 Cyclohexane, 1,1-diethoxy-, 65, 17 CYCLOHEXANE, 1,2-DIMETHYLENE, 65, 90... 

Additionally, benzoannelated cycloheptanes 54 were obtained in good yields (Scheme 18). It was also possible to extend the methodology to dis-ubstituted or benzoannelated iodo arenes as substrates, giving rise to the formation of various functionalized annelated cyclohexanes and cyclohexanes 55-61 (Scheme 19). 

Reactions with Iodine and Bromine. All the reactions discussed above proceed at limiting rates that are independent of the concentration and nature of the reactant. However, reactions of iodine with Mn2(CO)j0 (6) and Re2(C0)1g (30) proceed by paths that are first order in [I2] as well as by the [I2]-independent homolytic fission paths. P-donor substituents increase the rates of reaction with I2 by several orders of magnitude (31) so that they proceed rapidly even at room temperature. Thus reaction of Mn2(C0)g P(C6Hu53)2 is estimated to occur over 108 times faster than Mn2(C0)jQ by a path first order in [I2] at 25°C in cyclohexane. In all cases the reactions proceed with fission of the metal-metal bonds to form the mononuclear iodo complexes. 

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