SU433121A1 - ; <: GUSOB PREPARATION of ^ -PHENYLETHYL ALCOHOL - Google Patents

Description

one

The invention relates to methods for the synthesis of aromatic alcohols; in particular, D-phenylethyl alcohol, which constitutes 5% of the composition of natural rose oil, as well as is contained in nails of 1N1 geravine and non-ester oils. This may explain the great interest in the development of more accessible processes for the synthesis of α-phenylethyl alcohol.

A known method for producing α-phenyl ethyl alcohol by reacting ethylene oxide with benzene in the presence of an alkylating catalyst A1Cl. The process is carried out at a temperature of 5-6 ° C and a pressure of 44 O atm. However, the yield of α-phenylethyl alcohol from reactive pure ethylene oxide is relatively low (65–70%). In addition, ethylene oxide used for the oxyethylation of benzene must be highly concentrated, which is associated with great difficulties and costs.

The aim of the invention is to increase the yield of the target product. To achieve this goal, it is suggested that oxyethylation of benzene be carried out with dried contact gas.

obtained by direct oxidation of ethylene to ethylene oxide.

The process is preferably carried out at a temperature of 5-6 ° C and atmospheric pressure, with molar choros-carrying benzene: ethoxylate; fiSBHOM 4: 1, and the amount of catalyst is O, 25 mo e.

Carrying out the process under the conditions of supplying a large volume of contact gas, which constantly removes hydrogen chloride formed in the process, and atmospheric pressure allows to obtain the target product with a yield of 91-92% (the amount of by-product dibenzyl does not exceed 7-8% ), ethylene oxide conversion 1OO%.

In a three-necked flask equipped with a mechanical stirrer and reflux condenser, the calculated amount of dry benzene is loaded (m.p. 80.1 ° C; {1.20

2O, 879O; P. 1.5O11) and anhydrous

aluminum chloride. Dry, contact gas is fed through a glass tube into the reaction, cooled with ice water, with constant stirring.

The benzene hydroxyethylation reaction with contact gas is carried out at different molar ratios of benzene and ethylene oxide (1-2 O: 1-5) in the temperature range minus 5 - plus 4 O ° C with a reaction time of 1-20 hours and the amount of catalyst 1- 2O%, calculated on benzene taken into reaction.

It should be noted that unreacted benzene does not undergo any changes and can be returned to the cyclone. The contact gas exiting after the reaction is subjected to chromatographic analysis under the conditions used for the contact gas. The analysis shows. that ethylene oxide is completely reacted, and the other components remain unchanged.

; The resulting catalyzate is washed with distilled water until neutralized, dried with anhydrous magnesium sulphate and subjected to distillation. Unreacted benzyl oTJroHsaoT at atmospheric pressure, and the reaction products are under vacuum.

V

As a result of the reaction from catalyzate b), the following fractions:

T 80-8O, 1 ° С i P 91-92 С / 8 mm Hg. Art. W 138-139 ° C / 8 mm RT. Art. Loss balance

All the fractions obtained, except for the determination of their basic physicochemical constants, are subjected to chromatographic and IR spectroscopic analyzes. / I fraction according to physicochemical constants (m. Bale 80-8O, 1 ° С;

I am 20 4 20

1, so 12) represents

0.8792; P

D

unreacted benzene. Physico-chemical constants used for the reaction of benzene: so Kip, 8O, 1 C

2 °

9P

fl i.SOll. Chrome 4

O, 879 O;

J

Torrafichesky analysis of this fraction shows the presence of benzene only.

P fractions according to physico-chemical constants (m. Bale, 91-92 C / 8 mm Hg; Art .;

20

20

d

1.5299) prev1, 0253; (7) is phenyl ethyl alcohol. Physico-chemical constants jS-phenylethyl alcohol: so Kip, 98-1OO C /

25

/ 12 mmHg v .;

1.0235;

Claims (3)

1 16.18 - (5337, Mol. Century. J3-phenyl-, | ethyl alcohol: found 122, O1; You numbered 122,169. Found,%: C 78.59; H 8.27. Calculated,%: C 78.65; H 8.25. M r jj dl / -СНз-СЩ-ОН . found 36.70; calculated 37, On, Chromatographic analysis (analysis conditions: Color-1 apparatus, column length 3 m, column temperature 16O ° C, carrier gas — helium, liquid phase — silicone oil on TND ТСМ, Р 20 kg / cm) showed that this fraction consists of 98.5% J3-phenylethyl alcohol. The structure of the obtained ft-phenylethyl alcohol is proved by means of IR spectroscopic analysis (IKS-22). The presence of bands 3060, ZO2O, 161O, 1595, 745 and 695 and groups of bands in the area-1 1960-1740 cm indicates the presence of a mono-mixed ring, the band at 3440. cm-1 confirms the presence of a hydroxyl group, and the band at 1060 cm of the primary hydroxyl group. The P1 fraction is a symmetric diphenylethane, which has the following physicochemical constants: bale. ,50 138T-139 C / 8 mm Hg. CT.j 0.966 pc; P 1,5704. Mol c .: found 181,987 L is calculated 182,252. Found,%: C 92.16; H 7.81. Calculated,%: C 92.26; H 7.74. The structure of the obtained symmetric diphenylethane is determined by IR spectroscopy. Example 1. For the reaction using 234 g of benzene and ZOO l / h of contact gas. The composition of the contact gas; %: Ethylene oxide 1.45 Ethylene .1,5 COg1-0 Air 96.05 A1Cl is used in the amount of 23.4 o (10% in relation to benzene). The test is carried out at., The reaction time is 4 hours. After treatment, 239.9 g of catalyzate are obtained. During distillation, the following fractions are isolated: G (80-8O, 1 ° C) 207.8 g benzene 5 | I (91-92 ° C / 8 MMHg) 28, P-phenyl ethyl alcohol Residue 1.1 g Loss 2.5 g Example 2. 234 g of benzene and ZOO l / h of gas. Contact gas composition,%: Ethylene oxide Ethylene1,3, 0 Air96.05 23.3 g of A1C1 (1O% wear to benzene) are used. The test was conducted at 5 ° C, the reaction time was 4 hours. After treatment, 262.4 talizate is obtained. During distillation, the following fractions are isolated: T (8O-8O, 1 ° C) 169.2 g of benzene P (91-92 ° C: / 8 mmHg) 85.9 JJ-phenylethyl alcohol Residue 4.6 g. Loss of 2.7 g. Example 3. 234 g of benzene and 300 l / h of k gas are reacted for the reaction. Contact gas composition,%: Ethylene oxide 1.45 Ethylene1.5, 0 Air96.05 23.4 g of A1C1 (1O% wear to benzene) are used. The experiment was carried out at 2 ° C, the reaction time was 8 hours. After treatment, 268.3 talizate is obtained. During the distillation, the following fractions are isolated: - I (80-80.1 ° C) 155.4 g of benzene P {91-92 ° C / 8 mm Hg. Art.) 32.6-phenylamine alcohol I III {138-139 ° C / 8 mm Hg. Art.) 71.9 g. asymmetric diphenleethane Balance 5.6 g Loss 2.8 g Example 4: 234 g of benzene and ZOO l / h of contact gas, in which the content of ethylene oxide is 1.45%, are used for the reaction. 46.8 g of A1Cl are used. The test was carried out at 20 ° C, the reaction time was 4 hours. After treatment, 256.33 g of catalyzate are obtained. During distillation, the following fractions are isolated: 1 (8O-8O, 1 ° C) 174.1 g of benzene P (91-92 ° C / 8 mmHg) 5.1 g of phenyl ethyl alcohol And 138-139 ° C / 8 mm Hg. Art. 45.13 g of symmetric diphenylethane Residue 28.9 g Losses 3.1 g Subject of the invention 1. Method of preparing -phenylethyl. alcohol by oxyethylation of benzene in the presence of a catalyst — aluminum chloride — followed by separation of the target product by the known methods i, which is to ethylene oxide. 2. A method according to claim 1, characterized in that the process is carried out at a temperature of 5-6 ° C and atmospheric pressure. 3. A method according to claim 1, characterized in that. The process is conducted at a molar ratio of benzene: hydroxyethyl agent of 4: 1 and a catalyst amount of 0.25 mol.