Bromine mixing time with

The Step 5 product (6.55 g) dissolved in 75 ml CHC13 was treated with 1.53 ml bromine, then stirred 2 hours at 0°C, and concentrated. The residue was mixed with dilute HC1 and then extracted twice with diethyl ether. The aqueous phase was made alkaline with dilute NaOH and re-extracted three times with diethyl ether. The combined ether extracts were concentrated, the residue purified as described in Step 5, and 3.4 g product isolated as a white powder, mp = 157-158°C. 

For the identification of limonene, one of the most useful compounds is the crystalline tetrabromide, Cj(,HjgBr. This body is best prepared as follows the fraction of the oil containing much limonene is mixed with four times its volume of glacial acetic acid, and the mixture cooled in ice. Bromine is then added, drop by drop, so long as it becomes decolorised at once. The mixture is then allowed to stand until crystals separate. These are filtered off, pressed between porous paper, and recrystallised from acetic ether. Limonene tetrabromide melts at 104 5° and is optically active, its specific rotation being + 73 3°. The inactive, or dipeutene, tetrabromide melts at 124° to 125°. In the preparation of the tetrabromide traces of moisture are advisable, as the use of absolutely anhydrous material renders the compound very diflftcult to crystallise. 

Methyl-heptenone also forms a bromine derivative which is well suited for the identification of the ketone. This body, which has the formula CgHjjBrgO. OH, melts at 98° to 99°, and is obtained as follows Three grams of methyl-heptenone are mixed with a solution containing 3 grams of caustic soda, 12 grams of bromine, and 100 c c. of water. After a time an oily substance is deposited, which is extracted with ether. The solvent is evaporated, and the residue, redissolved in ether, is treated with animal charcoal and filtered. On slow evaporation the product is obtained in well-defined crystals. 

If a gram-atom each of iodine and bromine be mixed with a warm very cone, soln. containing a mol.. of potassium bromide, H. L. Wells and H. L. Wheeler found when the soln. is exposed for some time to a low temp., crystals of potassium dibromo-iodide, KBr2I, are formed. F. Ephraim found the dissociation press, of KIBr2 to be 5 mm. at 17° 15 mm. at 40° 47 mm. at 54 5° 98 mm. at 71° ... 

Prepare a little of a bromic acid solution. To do this, mix 2-3 drops of a saturated potassium bromate solution with 1-2 ml of a dilute sulphuric acid solution. Throw a minute iodine crystal into the solution, mix the test tube contents several times, decant the solution, and add several drops of an organic solvent to it. What is observed Write the equations of the reactions. Will bromine displace iodine from iodic acid ... 

Typical halogenation processes for making halobutyl rubbers involves the injection of chlorine or bromine into a solution of butyl rubber. The reactants are mixed vigorously in the halogenation reactor with a rather short resident time, typically less than 1 min, followed by the neutralization of the HC1 or HBr and removal of the unreacted halogen (13). The procedures of halogenation have been described in detail elsewhere (41,42). 

Gas-chromatographic analysis (column PEG-6000, 2 meters, column temperature 180°C., carrier gas, He) of the residue showed that it consisted of three main products. The first peak was identified as bicyclohexyl, the second as 3-cyclohexylcyclohexene, and the third as 3,3 -bicy-clohexenyl. The residue was distilled, and a fraction boiling at 90°-122°C./20 mm. Hg was collected. This fraction was poured into 10 times its volume of acetic acid. The solution was cooled to 0°C., and bromine was added. Colorless needle crystals and a red viscous oily liquid were obtained. The crystalline material was recrystallized from acetic acid and melted at 157.5°-160°C. (decomp.) [literature, 158°C. (6)]. A mixed melting point with an authetic tetrabromide of 3,3 -bicyclohexenyl was not depressed. 

When the solvent is methanol-benzene, the products 126 and 127 predominate. Their combined yield is 8.2 times greater than the yield of 128. However, when a bromine-containing solvent is mixed with the methanol, the... 

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