Bromo- cyclohexane

Cyclohexen-l-one, 3-methyl-, 53, 101 Cyclohexyl bromide [Cyclohexane, bromo ], 82... 

The synthesis of arene oxides 44, 46, and 47 via cyclohexane bromo-j3-lactone epoxide intermediates constitutes a novel synthetic approach to arene 2,3-oxides.Although the final consecutive dehydrobromination and thermal decarboxylation steps in the synthesis of 44,46, and 47 proceed under mild conditions, they do not, however, permit the isolation of 1 from the corresponding bromo- 3-lactone epoxide. 

A solution of 7-bromo-2-(fV-methylanilino)hept-2-enenitrile (145 mg, 0.52 mmol) in cyclohexane (60 ml) was placed in a quartz tube and purged with oxygen. The sample was irradiated for 8h in a Rayonet Model RPR-100 Reactor using 254 nm light. An oxygen atmosphere was maintained during... 

Absence of peroxides (b) 2 bromo 2 methylbutane (c) 2 bromobutane (d) 1 bromo 1 ethylcyclohexane Presence of peroxides (b) 1 bromo 2 methylbutane (c) 2 bromobutane (d) (1 bromoethyl)cyclohexane... 

By oxidation with chromic acid, this is converted into cyclohexanone-3-carboxylic acid, in which the —CH. OH— group is converted into the —CO— group. This is converted into its ethyl ester and treated with magnesium methyl iodide, and the product, on hydrolysis, yields l-methyl-cyclohexane-l-ol-3-carboxylic acid, which is converted byhydro-bromic acid into 1-bromo-l - methyl - cyclohexane - 3 - carboxylic acid. When this is digested with pyridine, hydrobromic acid is eliminated and yields l-methyl-A -cyclohexane-3-carboxylic acid of the formula—... 

Dipolar cycloadditkm reactions of nitrones to olefins, 46, 1,3-Dipolar cycloadditions with 3-phenylsydnone, 45, 98 Dispiro[5 1 5 l]tetradecane-7,14-dione, photolysis to cyclohexylidene-cyclohexane, 47, 34 preparation from cyclohexanecarbonyl chlonde and triethylamine, 47,34 Displacement of bromine from 1-bromo-2-fluoroheptane to give 2-fluoro-heptyl acetate, 46, 37... 

Hydrolysis, of 2 benzyl 2 carbometh oxycyclopentanone with lithium iodide m 2,4 6-colhdme, 46, 7 of 7 butyrolactone to ethyl y-bromo-butyrate with hydrogen bromide and ethanol, 46, 42 of 2,5 dicarbethoxy 1 4-cyclohexane-dione to 1,4 cyclohexanedione, 46, 25... 

Tndecanedione, 47, 95 Tnethylamine, 46, 18 dehydrobromination of o-bromo-y-butyrolactone with, 46, 23 dehydrobromination of or.a -dibromo-dibenzyl ketone, 47, 62 dehydrochlormation of cyclohexane-carbonyl chloride, 47, 34 in synthesis of nicotinic anhydride with phosgene, 47, 90 Tnethyl orthoformate, condensation with N,N diphenylethylene-diaminc, 47,14... 

A solution of 1 l,12-dihydrodibenzo[r,g][l,2]diazocine (1 1.5 g, 7.1 mmol) in CC14 (120mL) was stirred with NBS (1.5 g. 8.43 mmol) and refluxed for 12 h. The mixture was cooled and filtered, the filtrate was evaporated to dryness, and the resulting dark residue was extracted with boiling cyclohexane (100 mL). The extract was decolorized with charcoal and the filtrate was evaporated to dryness to afford crude 11-bromo-l l,12-dihydrodibenzo[c,g][l,2]diazocine (2) yield 1.1 g (54%) mp 105-106 C (after recrystallization from cyclohexane). 

What concerns us here are three topics addressing the fates of bromonium ions in solution and details of the mechanism for the addition reaction. In what follows, we will discuss the x-ray structure of the world s only known stable bromonium ion, that of adamantylideneadamantane, (Ad-Ad, 1) and show that it is capable of an extremely rapid degenerate transfer of Br+ in solution to an acceptor olefin. Second, we will discuss the use of secondary a-deuterium kinetic isotope effects (DKie) in mechanistic studies of the addition of Br2 to various deuterated cyclohexenes 2,2. Finally, we will explore the possibility of whether a bromonium ion, generated in solution from the solvolysis of traAU -2-bromo-l-[(trifluoromethanesulfonyl)oxy]cyclohexane 4, can be captured by Br on the Br+ of the bromonium ion, thereby generating olefin and Br2. This process would be... 

The chloro- and bromo-cyclohexane inclusion compounds have been extensively examined by infrared (4000-30 cm-1) spectroscopy65-68 and by Raman (< 1000 cm-1) spectroscopy 69). In the canals both guests are found to exist exclusively in the chair conformation with an axial halogen substituent, while iodocyclohexane 65, 68,69) acj0pts both axial and equatorial conformations in the canal. These results should be contrasted with the familiar situation in the liquid phase where the equatorial arrangement is the lowest energy conformer and is present to the extent of about 65-70% at room temperature. 

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. 

Fig. 41. 0(Q)/Q2 vs. Q for different dilute solutions under -conditions PDMS/d-bromo-benzene, T = 357 K x PS/d-methylcyclohexane T = 341 K O PS/d-cyclohexane T = 311 K...

Aluminum foil, Iodine powder. Carbon disulfide, 1,4,6,9-Tetrabromodiamantane, Sodium bisulfite. Hydrochloric acid. Methanol, Acetonitrile, Acetone, Sodium hydroxide. Magnesium sulfate. Potassium permanganate. Toluene Methylene chloride, 2-Bromomethanol, Trioxane, Aluminum chloride. Magnesium sulfate, Nitroform, Acetone, Sodium bicarbonate. Hexane, Silver nitrate. Acetonitrile 1,2-Dichloroethane, HexamethyldisUane, Iodine, Cyclohexane, 1,3-Dioxolane, Nitroform, Methylene chloride, Dimethylformamide, Sodium sulfate. Hydrochloric acid. Magnesium sulfate. Nitric acid. Sulfuric acid Sulfuryl chloride. Acetic anhydride. Nitric acid. Sodium bicarbonate. Sodium sulfate Nitric acid. Sulfuric acid, Malonamide Nitric acid. Sulfuric acid, Cyanoacetic acid Sulfuric acid, Acetasalicyclic acid. Potassium nitrate Nitroform, Diethyl ether, 1-Bromo-l-nitroethane, Sodium sulfuate... 

Using h NMR spectroscopy the complex-formation equihbria between halothane (2-bromo-2-chloro-l,l,l-trifluoroethane) and methyl tert-butyl ether or tetrahydrofu-ran in various inert solvents (hexane, heptane, decane, cyclohexane) were measured as a function of temperature (Tkadlecova et al., 1995). 

Thus, condensation with ethyl 4-bromo-3-methyl-2-butenoate (2E/2Z 50/50) provided the sulphone-ester, as a mixture of isomers (13 /13Z 50/50). Elimination to the ethyl 9-methylene-retinoate (2E/2Z 50/50) was done by treating the crude mixture with EtONa in cyclohexane, Fig. (42). 

Selective bromine-fluorine exchange of one bromine atom occurs in the reaction of tram-4,5-dibromo-m-cyclohexane-1.2-dicarboxylic anhydride (10) with sulfur tetrafluoride to give isomers of 5-bromo-l,l,3.3,7-pentafluoro-c/.v-octahydroisobenzofuran (11) and 4-bromo-5-fluoro-m-1.2-bis(trifluoromethyl)cyclohexane (12) in a 5 1 ratio and good total yield.11... 

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