CC BY
11
DOI - 10.32743/UniTech.2021.92.11.12571
DEVELOPMENT OF TECHNOLOGY FOR THE PRODUCTION OF ACETYLENE DIOLS AND THEIR VINYL ETHERS
Lola Yusupova
Doctor of Philosophy in tech. Sciences, (PhD), associate Professor, Tashkent Chemical-Technological Institute, Uzbekistan, Tashkent E-mail: [email protected]
Suvonkul Nurmonov
Doctor of technical science, professor, National University of Uzbekistan, Uzbekistan, Tashkent
Shoyunus Obidov
Senior teacher of the department of Chemical technology of oil and gas refining, Tashkent chemical-technological Institute, Uzbekistan, Tashkent
Siroj Andaev
Assistant of the department of Oil and Gas Processing Facilities, Tashkent State Technical University named after Islam Karimov,
Uzbekistan, Tashkent
Dostonbek Qahhorov
Assistant of the department of Oil and Gas Processing Facilities, Tashkent State Technical University named after Islam Karimov,
Uzbekistan, Tashkent
РАЗРАБОТКА ТЕХНОЛОГИИ ПРОИЗВОДСТВА ДИОЛОВ АЦЕТИЛЕНА
И ИХ ВИНИЛОВЫХ ЭФИРОВ
Юсупова Лола Азимовна
д-р философии по техн. наук, (PhD), доцент, Ташкентского химико-технологического института, Республика Узбекистан, г. Ташкент
Нурмонов Сувонкул Эрхонович
д-р техн. наук, профессор, Национального университета Узбекистана, Республика Узбекистан, г. Ташкент
Обидов Шоюнус Ботир угли
ст. преподаватель кафедры "Химическая технология переработки нефти и газа "
Ташкентского химико-технологического института, Республика Узбекистан, г. Ташкент
Андаев Сирож Рустамович
ассистент кафедры Объекты переработки нефти и газа Ташкентского Государственного Технического Университета имени Ислама Каримова,
Республика Узбекистан, г. Ташкент
Каххоров Достонбек Рустам угли
ассистент кафедры Объекты переработки нефти и газа Ташкентского Государственного Технического Университета имени Ислама Каримова,
Республика Узбекистан, г. Ташкент
Библиографическое описание: DEVELOPMENT OF TECHNOLOGY FOR THE PRODUCTION OF ACETYLENE DIOLS AND THEIR VINYL ETHERS // Universum: технические науки : электрон. научн. журн. Yusupova L. [и др.]. 2021. 11(92). URL: https://7universum. com/ru/tech/archive/item/125 71
ABSTRACT
The research work aims to elaborate on the technology of obtaining acetylene diols and their vinyl ethers. The reaction of formation mono-, divinyl ethers as a result of vinyl butyn-2-diol-1,4, by acetylene and the influence of solvents, the catalyst and its quantity, duration of reaction, temperatures were investigated. Reaction velocity was defined. Recommended vinyl-3-butyn-2-diol-1,4, acetylene in the presence of highly basic systems at atmospheric pressure.
АННОТАЦИЯ
Целью исследований является разработка технологии получения ацетилендиолов и их виниловых эфиров. Исследована реакция образования моно-, дивиниловых эфиров ацетиленом в результате образования винилбутин-2-диола-1,4, а также влияние растворителей, катализатора и его количества, продолжительности реакции, температуры. Определена скорость реакции. Рекомендуется винил-3-бутин-2-диол-1,4-ацетилен в присутствии высокоосновных систем при атмосферном давлении.
Keywords: butyn-2-diol-1,4, vinyl ethers, homogeneous catalysis, acetylenic diol, KOH-DMSO.
Ключевые слова: бутин-2-диол-1,4, виниловые эфиры, гомогенный катализ, ацетиленовый диол, КОН-ДМСО.
At present, acetylene-based products are used in chemical production and engineering, medicine, to obtain the growth of regulatory drugs and pesticides, light industry, perfumery, food and other fields [1,2,5,8]. Particular attention is paid to the technology for the production of vinyl ethers and, on their basis, new drugs, unique polymeric materials, high-quality solvents for radio engineering, as well as reagents for directed organic synthesis [3,4,10].
Butyne-2-diol-1,4, a valuable chemical compound, enters into many organic reactions, forming many promising
materials. Undoubtedly, in this aspect, the study of the vi-nylation reaction of butyn-2-diol-1,4 is of increased interest, since it has not yet been studied.
For the synthesis of various vinyl ethers for research purposes, Watanabe's transvinylation method of available vinyl ethers of alcohols and acids with other alcohols and diols in the presence of mercury, palladium, or iridium salts is widely used.
The second most important method for the synthesis of vinyl alkyl ethers is the acetal dealkoxylation reaction [2], which is usually accelerated by using various acid catalysts:
/OAlk д +
RR^HCR2 A > RR^=CR2OAlk + AlkOH
^OAlk
1 ^
R R , R = H, Alk, OAlk, ClAlk; R = H, R1+ R2 = cyclo - Alk A+= H3PO4, H3PO4 + C5H5N, CF3SO3SiMe3 + Et3N, p -MeC6H4SO3H, AlCh, FeCl3
1,2-Divinyloxy-1- and 1,2-divinyloxy-2-propenes (I), (II) were first obtained with a total yield of 68% upon heating (100-110 °C) glycerol and acetylene in the superbasic KOH- DMS, successfully proven in vinylation reactions. The synthesis of propenes (I) and (II) was carried out in an autoclave under acetylene pressure using a significant excess (90-130 mol %) of KOH to glycerol. Under these conditions, 4-vinyloxymethyl-2-methyl-1,3-dioxolane is also formed with a yield of up to 9% [14].
p-substituted vinyl ethers can also be obtained by isomerization of allyl ethers under the action of strong bases [9] or metal complex catalysts [9,11]. According to this method, in the presence of ruthenium complexes, monoalkyl ethers of diols are easily isomerized to the corresponding monovinyl (1-propenyl) ethers of diols [12]:
R'CH=CH-CHoOR
кат
R=
R'CH2-CH=CHOR O Ar BnO
O
SPh
R'=H, COOCH3
KaT=BuOK- ДМСО, (Ph^P^RuCb, (Ph^P^RhCl n—BuLi, hv
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For the synthesis of various vinyl ethers for research purposes, Watanabe's method of transvinylation of available vinyl ethers of alcohols and acids with other alcohols and diols in the presence of mercury, palladium, or iridium salts is widely used [6, 7].
It is known that the vinylation of saturated alcohols has been well studied, while that of acetylenic alcohols and diols has been insufficiently studied. Our research goal is to develop a technology for producing acetylene diols and their vinyl ethers.
Research and methodology
0.215 g of KOH and 40 ml of DMSO were placed in a flask equipped with a reflux condenser, a stirrer and a tube for supplying acetylene, then the mixture was heated with constant stirring to 97-100 °C, after which it was slowly cooled to 35 °C, 4.3 g (0,05 mol) butyn-2-diol-1,4 and acetylene was passed through the reaction mixture at a temperature of 110 °C.
After 8 hours, the process was stopped and, after cooling, the reaction mixture was extracted with ether
and dried with MgSO4. Then the solvent was distilled off and the distillation was carried out in the presence of the hydroquinone inhibitor. After that, a fraction with a boiling point of 177-178 °C was obtained (at 10 mm Hg) corresponding to 2.69 g of monovinyl ether of butyn-2-diol-1,4 with Bp = 92-93 °C (at 10 13 mm Hg).
Product yield - 2.69 g, 48.1% (of theory),
d20=O,87O g/cm3, < = 1,4615
Similarly to the above procedure, vinylation was carried out at various reaction times, temperatures and amounts of catalysts, which were also used as LiOH and NaOH.
Results and discussion
In this part of the study, an attempt was made to carry out the vinylation of butyn-2-diol-1,4 with acetylene in a super basic medium. It was found that in the reaction mono- and divinyl ethers of diol were formed. Reaction scheme:
ch
ch
^s=ö+ koh
k+
:o=s
\
.ch3 ch
oh
ch2-c=c-ch2-oh + kh oh
:o=s:
ch3 ch
oh
0 CH3
ch2- c= c—ch2- o к++ ^s=o- h2o oh " ch/ "
CH2-c=C-CH2-O к + HC=CH I ••
OH
CH2- C=C-CH2"O-C=C:K I 2 2 •• I I
OH H H
CH2- C=C-CH2-O- C=C:K I 2 2 •• I I
OH H H
CH2- C=C-CH2-ÖH OH
CH2- C=C-CH2-O- CH=CH2 + CH2- C=C-CH2-O- ^CK I - I 2 I I
OH OH H H
The role of the KOH-DMSO system in the implementation of the vinylation reaction is reduced to the formation of a highly basic low-solvated dimsil anion:
CH3 svCH3
KOH + XSX
I
s
\ s- s+ CH3 1 K SCCH33 jOH"
Разделенная ионная пара
H3C СНз
Ö
OH-
H3C
CH
S
Ö-'
+HO
димсил анион
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However, the role of DMSO is not limited to this. In the general case, changes in such factors as the dielectric constant of the medium, the degree of hydrogen
bonding, and others can play a significant role in the im plementation of reactions.
б
CH2-C=C—CH2-0—CH=CH2 + 0=S"6+
CH
CH
I
OH
/CH3
ch2-c=c—ch2-o—ch=ch2+o=sc • HO
I CH3 2
0K 3
0H
ch2-c=c—ch2-0-ch=ch2 + hc=ch-
ch2- c= c— ch2- o—ch= ch2
o-c—c"k+
I I hh
-h"
_k+> œ2- c= c— ch2- o— ch= ch2
o-ch=ch
The conditions and yields of the reaction products were presented in Table 1 on the example of vinylation of butyn-2-diol-1,4. As follows from the data obtained, the dependence of the yield of mono and divinyl ethers on temperature was significant: at 100-120 °C it is 49.4% and 70%, respectively.
The kinetics of the synthesis of vinyl ethers of bu-tyn-2-diol-1,4 were studied. The main factors were determined - the nature of the solvents, the temperature,
and the amount of catalyst that affect the course of the process. Benzene, dioxane, DMSO, and DMF were used as a solvent, and LiOH, NaOH, and KOH served as catalysts. It was revealed that the optimal solvent is DMSO, and the catalyst is KOH. The results obtained under these conditions are shown in Table 1.
Table 1.
Synthesis conditions and yield of vinylation products of butyn-2-diol-1,4
Experience Reagent ratio Temperature, °C Time, The yield of the vinyl ether
Diol 1, mol KOH, mole DMSO, ml hour of butyn-2-diol-1,4, %.
monovinyl divinyl
1 0,1 0,1 90 95 6 28,0 43,0
2 0,2 0,2 200 100 4 40,0 32,0
3 0,2 0,2 200 100 6 31,0 45,2
4 0,1 0,1 90 100 6 29,0 49,5
5 0,1 0,1 90 120 6 27,3 52,4
6 0,2 0,2 200 100 7 26,4 49,2
7 0,1 0,2 100 140 7 24,5 31,6
8 0,15 0,3 200 100 4 44,2 48,0
9 0.2 0,5 20 100 4 31 14,3
The influence of the nature of the catalysts on the In this case, the amount of catalyst was 5% by weight of
yield of vinyl ethers was also investigated (Table 2). alcohol.
Table 2.
Effect of the nature of the catalyst on vinylation of butyn-2-diol-1,4
Catalyst The yield of vinyl ethers of butyn-2-diol-1,4,%
monovinyl ether divinyl ether
LiOH 24,2 36,8
NaOH 35,3 38,4
KOH 27,1 43,4
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It can be seen from the results obtained that the nature of the alkaline catalyst affects the yields of butyn-2-diol-1,4 ethers. In the order of the used catalysts LiOH, NaOH, and KOH, their yields increase. The values for monovinyl ether were respectively: 24.2; 35.3 and 27.1%, and for divinyl ether 36.8; 38.4 and 43.4%.
Thus, in the synthesis of vinyl ethers, KOH was the most active catalyst in synergy with dimethyl sulfoxide.
The amount of catalyst also affects the product yield. To determine this factor, the influence of the amount of KOH in the range of 2-10% of the mass of butyn-2-diol-1,4 was investigated. The data obtained are shown in Table 3.
Table 3.
Effect of the amount of KOH catalyst on the product yield vinyl
The amount of catalyst KOH,% (based on the mass of butyn-2-diol-1,4) The yield of vinyl ethers of butyn-2-diol-1,4, %
monovinyl ether divinyl ether
2 34,0 3б,б
3 30,4 39,5
4 28,5 41,8
5 27,1 43,4
7 25,б 44,б
10 25,3 45,7
12 24,5 4б,8
15 24,0 47,3
It follows from Table 3 that with an increase in the content of the catalyst in the studied interval, the yield of monovinyl ether of butyn-2-diol-1,4 noticeably decreases from 34.0 to 24.0%, respectively. A further increase in the amount of catalyst does not significantly affect the product yields.
With an increase in the amount of catalyst, the yield of divinyl ether increases symbiotically. This fact is explained by the fact that in the process, monovinyl ether
was first formed. An increase in the yield of divinyl ether always leads to a decrease in the yield of butyn-2-diol-1,4 monovinyl ether.
When the reaction was carried out under homogeneous conditions, the product yield and the selectivity of catalytic systems were significantly affected by the nature of the solvent. Data on the study of the effect of the nature of solvents (benzene, dioxane, DMSO, DMF) on the yield of the reaction product were given in Table 4.
Table 4.
Influence of the nature of solvents on the yield of monovinyl ether of butyn-2-diol-1,4. (The reaction time is 8 hours, the temperature is 130 ° C, the catalyst is KOH (5%)).
Solvent Product yield,%
monovinyl ether divinyl ether
Benzene 12,5 5,4
Dioxan 20,б 15,3
DMFA 29,5 32,б
DMSO 27,1 43,4
Of the solvents used, DMSO was found to be the most suitable. In its presence, the yields of mono- and divinyl ethers are, respectively, 27.1 and 43.4%.
The role of DMSO boils down to the fact that, firstly, acetylene dissolves well in it, and secondly, it forms a super-basic system with KOH. In this case, the basicity of KOH increases due to the separation of ion
pairs. Vinyl ethers were formed by nucleophilic addition of diol mono- and di-potassium alcoholate.
It is known that the reaction time and temperature have a great influence on the product yield. In this regard, the effect of temperature (in the range of 100-150 °C) and reaction time (4-10 hours) on vinylation of butyn-2-diol-1,4 in the presence of KOH was also studied (Table 5).
Table 5.
Influence of the reaction time and temperature on the yield of butyn-2-diol-1,4 divinyl ether (DMSO solvent, KOH catalyst in an amount of 5% by weight of alcohol)
Reaction time, hour Temperature, оС The yield of divinyl ether butyn-2-diol-1,4; %
4 100 25,6
6 100 33,2
8 100 35,7
10 100 37,5
4 120 27,5
6 120 40,5
8 120 46,0
10 120 47,4
4 130 32,3
6 130 38,6
8 130 43,4
10 130 49,2
4 150 30,0
6 150 36,6
8 150 47,0
10 150 47,3
To identify the dynamics of the process and improve its preparative characteristics, kinetic experiments were carried out. Fig. 4 shows the curves reflecting the change in the concentration of mono - (2) and divinyl (1) ethers of butyn-2-diol-1,4. The appearance of the obtained kinetic curves corresponds to a simple sequential reaction: the initially formed monovinyl ether easily binds to the second acetylene molecule to form divinyl ether, the
concentration of which gradually increases and after 56 hours reaches a plateau (Curve 1).
The maximum on the kinetic curve of monovinyl ether was reached after 2 hours (curve 2). At elevated temperatures (110-140 °C), favourable conditions were created for the detected elimination of acetylene from the divinyl ether.
Figure 4. Kinetic curves of the accumulation of divinyl (1) and monovinyl (2) ethers during the vinylation of butyn-2-diol-1,4 in the KOH-DMSO system at a temperature of 95 °C and a ratio of diol: KOH = 1:1
It follows from the table that with an increase in the duration of the reaction at all temperatures studied, the yield of vinyl ether passes through a maximum.
It should be noted that with an increase in the process temperature, the optimal value of the reaction time decreases. For example, at a temperature of 100 °C with an increase in the reaction time from 4 to 6 hours, the yield of the product increases from 25.6 to 33.2%, and at 150 °C in the range of 4-8 hours, the yield of ether increases from 30 to 47.0%.
The study of the effect of temperature in the range of 100-150 °C showed that the product yield passes through a maximum. The maximum yield (49.2%) of butyne-2-diol-1,4 divinyl ether was observed at 130 °C and its partial polymerization occurs.
Thus, the optimal conditions for vinylation of bu-tyn-2-diol-1,4 are the reaction time of 10 hours and the temperature of 130 oC.
The effect of the nature of the catalyst on the yield of butyn-2-diol-1,4 divinyl ether (temperature 130 °C, solvent DMSO) was also studied. LiOH, NaOH, and KOH were used as catalysts. The results were shown in Table 6.
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Table 6.
Influence of the nature of the catalyst on the yield of vinyl ether butyn-2-diol-1,4 (temperature 130 °C, solvent DMSO)
Catalyst Reaction time, hour Divinyl ether yield butyn-2-diol-1,4,%
4 19,4
6 22,0
LiOH 8 24,2
10 24,6
4 28,6
6 32,2
NaOH 8 35,3
10 36,8
4 32,3
6 38,6
KOH 8 43,4
10 49,2
It was found that with an increase in the duration of the reaction in the range of 4-10 hours in all cases, the product yield increases.
Among the catalysts used, the highest yield was achieved with the use of KOH. It follows from this that the greater the basicity of the catalyst, the higher the likelihood of its positive effect on the product yield.
The yield of the products and their purity were determined by gas-liquid chromatography. In fig. 1 shows the gas-liquid chromatogram of the catalyzate formed upon
vinylation of butyn-2-diol-1,4 with acetylene. It was shown that the catalyzate contains vinyl ether of butyn-2-diol-1,4 (1,2), unreacted butyn-2-diol-1,4 (3), solvent DMSO (4), and a small amount of a substance of an unknown structure.
In fig. 2 shows the chromatogram of the synthesized vinyl ether of butyn-2-diol-1,4. The kinetics of the synthesis of the vinyl ether of butyn-2-diol-1,4 has been studied (Table 7).
Figure 2. Gas-liquid chromatogram of the catalyzate of the vinylation reaction of butyn-2-diol-1,4
1: butyn-2-diol-1,4 divinyl ether; 2: butyn-2-diol-1,4 monovinyl ether; 3: butyn-2-diol-1,4; 4: solvent is DMSO.
Figure. 3. Gas-liquid chromatogram of butyn-2-diol-1,4 divinyl ether
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Table 7.
Kinetic data for the synthesis of the vinyl ether of butyn-2-diol-1,4 (catalyst KOH, 5% by weight of alcohol, solvent DMSO)
Reaction time, hour Temperature, оС The yield of di-VE bu-tyne-2-diol-1,4 Average reaction rate
% mol / L %/hour mol / l. hour. (W) lgW 1+lgW
4 100 25,6 0,3 6,4 0,48 -0,32 0,68
120 27,5 0,35 6,875 0,6 -0,22 0,79
130 32,3 0,4 8,075 0,8 -0,097 0,903
150 30,0 0,38 7,5 0,7 0,155 0,845
6 100 33,2 0,4 4,3 0,29 -0,54 0,46
120 40,5 0,5 6,75 0,56 -0,25 0,75
130 43,7 0,55 7,3 0,67 -0,17 0,83
150 36,6 0,46 6,1 0,47 -0,328 0,673
8 100 35,7 0,45 4,5 0,25 -0,602 0,398
120 46,0 0,57 5,75 0,41 -0,33 0,67
130 48,1 0,6 6,01 0,45 -0,35 0,65
150 47,0 0,58 5,8 0,42 -0,37 0,63
10 100 37,5 0,46 3,75 0,172 -0,77 0,23
120 47,4 0,59 4,74 0,28 -0,55 0,45
130 49,2 0,6 4,92 0,29 -0,54 0,46
150 47,3 0,59 4,73 0,28 -0,55 0,45
Based on the results obtained, the dependence of lgW on 1/T was constructed (Fig. 3) and, according to
the Arrhenius equation, the value of the activation energy for the formation of the divinyl ether of butyn-2' diol-1,4 was calculated, which is 51.7 kJ/mol.
Figure 4. Dependence of lgW on 1 / T in the formation of divinyl ether of butyn-2-diol-1,4
Conclusion
The optimal conditions for vinylation of butyn-2-diol-1,4 providing the maximum yield of butyn-2-diol-1,4 divinyl ether were determined. The best effect as a solvent among the investigated benzene, dimethyl sulfoxide, has dimethyl sulfoxide. With an increase in the
reaction time, the yield of divinyl ether increases, reaching a maximum after 8 hours. The relatively low value of the calculated activation energy, equal to 51.7 kJ / mol, indicates a fairly high rate of the vinylation reaction of butyn-2-diol-1,4.
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