SK387892A3 - Method of production 1-bromine-3-chlorpropane and device for its realization - Google Patents

Description

The process is carried out by antimarker hydrobromination of allyl chloride at -10 to + 50 ° C, at a molar ratio of allyl chloride: hydrogen bromide of -1: 0.7 to 5 in a liquid anhydrous medium, in the presence of oxygen or a mixture of oxygen with organic peroxide and / or hydroperoxide. 0.05 to 10% by weight, calculated on the weight of allyl chloride. The main product is separated by distillation and / or rectification. The process can be carried out batchwise, semi-continuously and continuously.

PvIII-J2

-1- ¹

Method of production. I-bromo-3-chloropropane. and an apparatus for carrying it out.

Technique area

The invention relates to a process for the production of 1-bromo-3-chloropropane as an important organic intermediate, by a high-selective hydrabaromation; allyl chloride such as: i. especially continuous production.

BACKGROUND OF THE INVENTION.

1-Bromo-3-chloropropane is. an important intermediate, useful especially in the manufacture of pharmacists, as well as several important organic products.

It can be produced by telomerization of ethylene with bromochlopoethane (Afanase v. I.B., Beer A. A .: Žur. Vsesojuz. Chim. Ob. I. Mendeleleeva 1962, p. 595; USSR Authorized Certificate 187 749). However, it requires technically more difficult, available bromochloromethane and yields. no: they are satisfactory. So most attention was paid to the addition of dry hydrogen bromide against Markovnikov's rule to allyl chloride:

ClCl 2 Cl 2 + -HBr -ClCH ₂ CH ₂ CH ₂ Br, wherein ¹ , to a greater or lesser extent in accordance with Markovnikov's rule, also produces 1-chloro-2-bromopropane CHCl 3 Cl 2 · ClCH ₂ CH ( Br) CH 2 / Kharasch MS, Mayo FR: J. Am. Chenu Soc. 55, 2468 (1933); ibid. 62, 2047 (1940); Beilsteins HanchLuch der organischen Chemie, I. edition, I. vol. 10, s: 1Ô9; Beisteins- II., Appendices, Volume I III III, p. 75; Ibid. III, Appendices, i. Volume E III 1, p. 245; Kirk-Othmer: Ency-clopedia-of. Chemical Technology, 3th edition, Volume 1, p.

254; 2nd edition. , 3rd volume, p. However, a yield not exceeding 1-bromo-3-chloropropane is achieved. 43% · Progress has been made in the irradiation of ultraviolet light of analyl chloride / Ancus L. I .: 2ur. Ex. chim. 2053 (1936); Magidson S. Ju. E.T. al .: ibid. However, the reaction rate is lower and the technical scale is also demanding from a safety point of view. Similar technical problems and low5

The selectivity reduces the attractiveness of other preparation procedures as well

Aluminium chloride under the catalytic effect of aluminum bromide at 2 to

5 ° C as well as the reaction of allyl chloride with a gas of lightning gas under the catalytic action of chloride, bismuth at 21 ° C (U.S. Pat. Nos. 2,302,228 and 2,255,605) or Paraldehyde and other low-molecular aldehydes (U.S. Pat. ). Of newer patents, hydrobromation of olefinically unsaturated compounds is of interest. radiation treatment to the mixture _and hydrogen bromide and organic compound; by light with a wavelength of 335 to 500 nm / Zelovich J. et.

Claims (1)

Example 8 The procedure is as in Example 7, l ^en initiator antimarkovnikovovskej addition of hydrogen bromide to the allyl chloride, the supply of district 3L7 cm ^ / min of molecular oxygen, the. at the start of the experiment, 0.15 g of bis (2-chloroisopropylperoxycarbonate) and 0.15 g of tert. In 60 minutes the conversion of allyl chloride is 96.5%, the selectivity to 1-bromo-3 * chloropropane 96.3% and to 1-chloro-2-bromopropane 3.2%. After 90 min the conversion of allyl chloride reaches 100.5%. % and selectivity 96.2, respectively. 3.3 * · Example 9 In FIG. 1 is a schematic diagram of a laboratory apparatus particularly at -8continuous preparation; l-bromo-3-chloropropane. . In FIG. 1 apparatus 1 represents a hydrogen bromide reservoir, e.g. cylinder containing dry hydrogen bromide. It is further comprised of scales 2, needle needle valves (J), capillary tubes (4), flow meters for hydrogen bromide and oxygen (6), valves (2) for the oxygen supply line and for the oxygen line. the oxygen-containing gas 8, the reservoir, respectively. Allyl chloride or allyl chloride-containing allyl chloride or allyl chloride-containing conduit 11 containing, by means of a pump 10, a jacketed glass reactor 12 ' provided with a thermometer 13 ' containing large glass Rashig rings and perforated at the bottom: a circular inlet for hydrogen bromide. hydrogen bromide with an oxygen-containing gas line. 6, dark cells or thermometers 14 measuring and regulating the temperature; in the jacket of the reactor 12, the thermostat, respectively. inlet: cold water 15. recirculated coolant line 16. coolant line 12, raw product outlet; hydrobromation-18, hydrogen bromide gas separator and calibrated? intermediate feedstock of the 19th feed. stripping gas 20, removal of optionally unconverted hydrogen bromide and allyl chloride 21 ' a pair of possibly unconverted allyl alcohol, via a chiller-capacitor 22 ' alyl chloride ·, by pipeline, 30 to · · tank, intermediate tanks or directly for distillation, respectively. rectification. Removal of unconverted bro · * hydrogen hydrogen i s. possible oxygen additions, piping. 24 «optionally. also by the blower 25 and the conduit 22 being either current; fresh? hydrogen bromide and oxygen 6 or, directly to the reactor or, in addition: via line 26 through flow meter 5 via line 27 to? fresh hydrogen bromide pipes, generally with oxygen; 6, or until absorption (absorber) 28 with an aqueous solution of sodium hydroxide and not absorbed oxygen, and. Inert line 29 to off-gas. Workflow: Lck reactor 12 is first pumped 6O0g, crude: product hydrobramácie allyl chloride-containing materials .. 90.3% 1-bromo-3-chlorpropán.u, 4, 5 weight% of L ^*-chloro: or 2-bromopropane and 5.2% by weight of the mixture. dibromochloropropanes and other unidentified substances; which is brought to ^: 10 ° C by means of thermostat 15 and transported cold medium by pipeline. 17 and recirculated brine by line 16. Then, start from. button _(coffee; j of the bottle 1 through a pressure reducing valve. J, and a capillary flow-4% of commercial feed. 13.6 grams / minute of hydrogen bromide. to a. · the current. O line. 8 through a pressure "valve, at 1, 1 g / min of oxygen together to fall into the reactor 12 where they are scattered by means of a circular distributor with 50 orifices of 0.08 mm in diameter for good contact with the reaction medium. The pump pumped 10 g / min of allyl chloride to the bottom of the reactor 12. The reaction temperature was maintained at 10 ° C by means of a cooled reactor jacket with brine cooled in a thermostate 15, which also included a cooling device and recirculation via lines 16- and 17. After 3 hours of reaction, the amount of oxygen supplied is reduced to 0.55 g / min under otherwise identical conditions, via line 18 the crude product is discharged through the condenser-condenser 22 to the intermediate reservoir 19 and at the same time to the separator, uncontrolled. and partly acidic Calif., which additionally vystripovávajú air supply pipe 20 'The stripped hromovodík i s. the oxygen-containing gas is discharged via line 21 through a condenser-condenser 22 therefrom via a droplet of entrained droplets of crude; product, or the raw product stream · 23 through a pipe 30 to. a reservoir of raw, product, or stream; of the crude product from the intermediate tank 20 'leading to distillation and rectification. At the same time, from the stream, the crude product is added by adding small amounts of sodium bicarbonate. n na na; neutralization of any hydrogen bromide present in the gas-liquid chromatography column, on-line. The optionally converted allyl chloride, 1-bromo-3-chloropropane, 1-chloro-2-bromopropane and dibromochloropropanes are determined. Excess hydrogen bromide is It passes through line 24 to the absorber 48 where the aqueous hydroxide solution. sodium bromide reacts and mesconverted