Preparation of chlorobenzene
Preparation of chlorobenzene by Sandmeyer’s method
31 g of aniline are dissolved in 200 ml of water and 57 ml of concentrated hydrochloric acid. Slowly to the solution 23 g of sodium nitrite dissolved in 60 ml of water are added. The obtained solution is slowly run into 350 ml of an almost boiling 10 %, cuprous chloride (CuCl) solution. After the reaction is complete the aqueous liquid is separated, and the residual crude oily chlorobenzene is steam-distilled. The oil which passes over is collected, washed with dilute sodium carbonate, then with water, dried over calcium chloride, and finally distilled yielding 73 % of colorless liquid boiling at 132° C.
Preparation of chlorobenzene by Gattermann’s Method
31 g of aniline are added to 150 ml of water and 225 ml of concentrated hydrochloric acid. Complete solution does not take place. The resulting liquid is diazotized with 23 g of nitrite. 40 g of elemental copper powder are added, and the reaction mixture is allowed to stand until the reaction is over (about 30 min.). After reaction is complete elemental copper will collect to the bottom of the flaks. The chlorobenzene is purified by steam-distillation. The oil which passes over is collected, washed with dilute sodium carbonate, then with water, dried over calcium chloride. Yield is about 73 %.
Preparation of organic compounds, E. de. Barry Barnett, 76-77, 1912
Preparation of chlorobenzene by direct chlorination of benzene with chlorine
Chlorination reaction of benzene is best carried out at about 30° C. At lower temperatures, the reaction proceeds slowly, meanwhile at higher temperatures by-products, such as polychlorobenzenes, form. Chlorine is taken from a cylinder or could be generated by treating manganese dioxide, potassium dichromate, potassium permanganate with concentrated hydrochloric acid. During the chlorination it is important to exclude moisture, since even traces of water reduce the absorption of chlorine and favor the formation of by-products. In order to remove any moisture from chlorine, the gas is passed trough at least two washing bottles containing concentrated sulfuric acid. A relatively tall and narrow glass cylinder may be used advantageously as a chlorination vessel, yielding greater contact area between gas and liquid. The reaction flask is placed in a water bath and is fitted with an efficient reflux condenser. The hydrogen chloride escaping from the condenser is absorbed in a round-bottomed flask containing sodium hydroxide or water. In addition, the tube from the condenser should placed directly above the surface of the absorption liquid, and should not dip into the solution.
To a 500 ml chlorination flask 312 g (or 4 moles) dry benzene, 5 g iron powder are placed and a vigorous stream of chlorine is passed. After a considerable quantity of chlorine has dissolved in the benzene the reaction starts by a sudden rise in temperature. The stream of chlorine is reduced and the flow of cooling water is started, after which the introduction of chlorine is again accelerated by maintaining reaction temperature at about 30°C. A very rapid stream of chlorine should be avoided as it leads to incomplete absorption of the gas. Efficient cooling in the reflux condenser is necessary in order to prevent benzene from escaping with hydrogen chloride. The hydrogen chloride formed in the reaction is led into a 2 liter flask which contains sodium hydroxide solution or water. The progress of the chlorination reaction is determined by weighing the reaction flask. The reaction is complete when 80 % of the chlorine calculated as necessary for the formation of monochlorobenzene has been absorbed and the weight of the reaction flask is increased by 117 g. If the chlorination is continued higher chlorination products form rapidly. Iron is allowed to settle and the liquid is decanted into a separatory funnel where it is washed thoroughly with dilute hydrochloric acid, then with sodium hydroxide solution, and finally with water. Around 410-420 g of obtained chlorobenzene are purified by fractional distillation, in vacuum or at atmospheric pressure and using very efficient (at least 60 cm high) column filled with glass rings. At atmospheric pressure the following fractions are obtained:
1) 70-100° C, benzene with a little chlorobenzene. Yield is about 70 g.
2) 120-130° C, almost pure chlorobenzene. Yield about 295 g.
At 9 mm of mercury pressure the following fractions are obtained:
3) up to 55° C, mono- and dichlorobenzene. Yield about 10 g.
4) 55.5° C, o- and p-dichlorobenzene. Yield about 40 g.
5) higher boiling products and residue, very small amount.
By cooling fraction 4 to about 10° C and centrifuging, about 12 g of pure p-dichlorobenzene can be obtained.
The yield of monochlorobenzene is 295 g or 65% based on the benzene.
The fundamental processes of dye chemistry, by H. E. Fierz-David, 62-63, 1949
CHLOROBENZENE, Monochlorobenzene, Benzene chloride, Benzene, chloro-, Phenyl chloride, 108-90-7, Chlorobenzol, Chlorbenzene, Chlorbenzol, Monochlorbenzol, Chlorobenzen, Clorobenzene, Monochlorbenzene, Chloorbenzeen, Chlorobenzene, mono-, chloro-benzene, Monoclorobenzene, Monochloorbenzeen, Tetrosin SP, Chlorobenzenu, chloranylbenzene, chloro benzene, NCI-C54886, PhCl, Chloorbenzeen [Dutch], Chlorobenzen [Polish], Chlorobenzenu [Czech], Caswell No. 183A, Clorobenzene [Italian], CP 27, I P Carrier T 40, Monochlorbenzol [German], NSC 8433, Monochloorbenzeen [Dutch], Monoclorobenzene [Italian], RCRA waste no. U037, HSDB 55, UNII-K18102WN1G, CCRIS 1357, CHEBI:28097, 4-chloro-benzene, MVPPADPHJFYWMZ-UHFFFAOYSA-N, K18102WN1G, EINECS 203-628-5, SBB040899, UN1134, EPA Pesticide Chemical Code 056504, MCB, AI3-07776, Chlorobenzene-UL-14C, Chlorinated benzenes, Benzene, chloro derivs., Monochlorobenzol, 1-chlorobenzene, 3-chlorobenzene, 4-chlorobenzene, Chlorobenzene Mono, Abluton T30, Benzene, chlorinated, IP Carrier T 40, AC1L1PYI, DSSTox_CID_298, CHLOROBENZENE, ACS, CHLOROBENZENE- D5, WLN: GR, ACMC-1BUC8, bmse001030, SCHEMBL2044, DSSTox_RID_75497, DSSTox_GSID_20298, 48506_SUPELCO, BIDD:ER0289, CHEMBL16200, 101389_ALDRICH, 270644_ALDRICH, 284513_ALDRICH, 08650_FLUKA, 23568_FLUKA, 23570_FLUKA, NSC8433, 312274_SIGMA, MolPort-000-872-062, 23568_SIAL, 23570_SIAL, LS-18, 101389_SIAL, 270644_SIAL, 284513_SIAL, 319996_SIAL, NSC-8433, EINECS 270-127-6, Tox21_201223, ANW-15992, STL282731, ZINC00896527, AKOS000120122, MCULE-2469021740, RP19079, RTR-002006, UN 1134, NCGC00091678-01, NCGC00091678-02, NCGC00258775-01, 68411-45-0, AN-42914, CAS-108-90-7, KB-76052, ZB015093, TR-002006, C1948, Chlorobenzene [UN1134] [Flammable liquid], FT-0615503, FT-0623633, FT-0652436, FT-0657623, S0645, ST50214500, X5840, Chlorobenzene [UN1134] [Flammable liquid], 5773-EP2269986A1, 5773-EP2269990A1, 5773-EP2269995A1, 5773-EP2270004A1, 5773-EP2270101A1, 5773-EP2270113A1, 5773-EP2272813A2, 5773-EP2272832A1, 5773-EP2272849A1, 5773-EP2272935A1, 5773-EP2274983A1, 5773-EP2275395A2, 5773-EP2275403A1, 5773-EP2275407A1, 5773-EP2275409A1, 5773-EP2275411A2, 5773-EP2275469A1, 5773-EP2279750A1, 5773-EP2280001A1, 5773-EP2280005A1, 5773-EP2281817A1, 5773-EP2281821A1, 5773-EP2284165A1, 5773-EP2284174A1, 5773-EP2286811A1, 5773-EP2287155A1, 5773-EP2287167A1, 5773-EP2287940A1, 5773-EP2289509A2, 5773-EP2289868A1, 5773-EP2289884A1, 5773-EP2289890A1, 5773-EP2289965A1, 5773-EP2292592A1, 5773-EP2292597A1, 5773-EP2292606A1, 5773-EP2295414A1, 5773-EP2295425A1, 5773-EP2295426A1, 5773-EP2295427A1, 5773-EP2298729A1, 5773-EP2298735A1, 5773-EP2298745A1, 5773-EP2298746A1, 5773-EP2298755A1, 5773-EP2298756A1, 5773-EP2298763A1, 5773-EP2298768A1, 5773-EP2298770A1, 5773-EP2298828A1, 5773-EP2301918A1, 5773-EP2301924A1, 5773-EP2301934A1, 5773-EP2301983A1, 5773-EP2305649A1, 5773-EP2305658A1, 5773-EP2305667A2, 5773-EP2305673A1, 5773-EP2305675A1, 5773-EP2305682A1, 5773-EP2308838A1, 5773-EP2308849A1, 5773-EP2308850A1, 5773-EP2308857A1, 5773-EP2308879A1, 5773-EP2308882A1, 5773-EP2308926A1, 5773-EP2309564A1, 5773-EP2309584A1, 5773-EP2311804A2, 5773-EP2311808A1, 5773-EP2311809A1, 5773-EP2311811A1, 5773-EP2311813A1, 5773-EP2311829A1, 5773-EP2311834A1, 5773-EP2314558A1, 5773-EP2314574A1, 5773-EP2314577A1, 5773-EP2314581A1, 5773-EP2371808A1, 5773-EP2371831A1, 5773-EP2374783A1, 5773-EP2374895A1, 5773-EP2377610A2, 5773-EP2377611A2, 5773-EP2377841A1, 5773-EP2380568A1, C06990, EC 203-628-5, 37376-EP2311802A1, 37376-EP2311803A1, 77825-EP2272846A1, 77825-EP2277868A1, 77825-EP2277869A1, 77825-EP2277870A1, 77825-EP2284166A1, 77825-EP2292608A1, 77825-EP2295436A1, 77825-EP2298749A1, 77825-EP2298769A1, 77825-EP2308866A1, 77825-EP2371806A1, 77825-EP2371807A1, 77825-EP2374784A1, 77825-EP2374785A1, 152544-EP2269986A1, 152544-EP2289896A1, 152544-EP2289897A1, 152544-EP2371831A1, A801940, 3B4-0476, I01-1941, InChI=1/C6H5Cl/c7-6-4-2-1-3-5-6/h1-5, 50717-45-8, 8CL
CHLOROCYCLOHEXANE, CID7964, c0105, C031294, 542-18-7, 3114-55-4