GB2176801A - Liquid-phase dehydration of aromatic alcohols - Google Patents
Liquid-phase dehydration of aromatic alcohols Download PDFInfo
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- GB2176801A GB2176801A GB08614739A GB8614739A GB2176801A GB 2176801 A GB2176801 A GB 2176801A GB 08614739 A GB08614739 A GB 08614739A GB 8614739 A GB8614739 A GB 8614739A GB 2176801 A GB2176801 A GB 2176801A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
- C07C1/20—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms
- C07C1/24—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms by elimination of water
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2521/00—Catalysts comprising the elements, oxides or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium or hafnium
- C07C2521/12—Silica and alumina
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2529/00—Catalysts comprising molecular sieves
- C07C2529/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites, pillared clays
- C07C2529/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Catalysts (AREA)
Abstract
A process for preparing an aromatic vinyl compound of the formula <IMAGE> wherein Ar is phenyl, 1-naphthyl or 2-naphthyl and R is H or methyl, which comprises the liquid-phase dehydration, by heating, of an aromatic alcohol of the formula <IMAGE> wherein Ar and R are as defined above, in the presence of a solid acid catalyst.
Description
SPECIFICATION
Liquid-base dehydration of aromatic alcohols
The present invention relates to the liquid-phase dehydration of aromatic alcohols. A process of this type can be used to convert an aromatic alcohol of formula I to an aromatic vinyl compound of formula II.
The synthesis of olefins by the dehydration of alcohols is well-known, using sulphuric acid, phosphoric acid or zinc chloride-hydrochloric acid as the catalyst in a liquid-phase reaction, and a catalyst such as alumina in a gas-phase reaction. The considerable disadvantage of the given liquid-phase catalysts is that their use leads to the formation of a large amount of the by-product of formula III.
Nevertheless, it is very desirable to produce compounds of formula 11, suitably from aromatic alcohols of formula I, on an industrial scale. For example, 2-isopropenylnaphthalene is a product which can be used to improve the heat-resistance of ABS resin, as disclosed in Japanese Laid
Open Patent Application No. 58-108244 (1983).
According to the present invention, a formula I aromatic alcohol is subjected to liquid-phase dehydration, with heating, in the presence of a solid acid catalyst, to produce a formula Il aromatic vinyl compound. Ar is phenyl, 1-naphthyl or 2-naphthyl and R is H or methyl.
The present invention is particularly useful for producing high-boiling vinyl compounds, such as 2-isopropenylnaphthalene, on an industrial scale.
The process of the present invention can be conducted with or without a solvent.
Compound I, i.e. the aromatic alcohol, can be produced by oxidising the corresponding hydrocarbon, using molecular oxygen or air, in the presence of aqueous alkali.
In the process according to the present invention, the compound (I) is reacted without using any solvent or in a solvent while using a solid acid as a catalyst.
Namely, in the process according to the present invention, the use of a solvent is not necessarily inevitable, however, it is preferable to use a solvent for controlling the reaction temperature. As the solvent, hexane, heptane, benzene, toluene or xylene, preferably toluene or xylene may be used.
In addition, an aromatic hydrocarbon which is a raw material for producing the compound (I), as the solvent for the reaction of dehydration may be used. For instance, 2-isopropylnaphthalene may be used as the solvent in the dehydration of 2-(2-naphthyl)-2-propanol.
Further, in the case where a solvent having a higher boiling point than that of the product of dehydration is selected, such a solvent is favorable because the reaction product can be separated from the such solvent by distillation. For instance, in the case of producing a-methylstyrene, 2-isopropylnaphthalene is suitable as the solvent in the reaction, and in the case of producing 2-isopropenylnaphthalene, 2,6-diisopropylnaphthalene, 2,7-diisopropylnaphthalene or a mixture of 2,6- and 2,7-diisopropylnaphthalene is suitable as the solvent in the reaction.
In carrying out the process according to the present invention, the solvent is used in an amount of 0.5 to 20 times by volume, preferably 1 to 10 times by volume of the weight of the raw material.
In carrying out the process according to the present invention, a solid acid mainly composed of a mixed oxide of silicon and aluminum is used as a catalyst. Although solid acid catalyst such as aluminum silicate, diatomite, active terra alba, H-type synthetic zeolite and the like is suitable for the process according to the present invention, according to the present inventors' finding, the ratio of proceeding of dehydration and dimerization is determined by the density of so-called Brónsted acid on the surface of the solid acid catalyst.
Namely, in the case where the catalyst high in the density of Brdnsted acid is used, dehydration mainly proceeds, and on the other hand, in the case where the catalyst low in the density of Brdnsted acid is used, dimerization mainly proceeds. Aluminum silicate and H-type synthetic zeolite which is high in the density of Brónsted acid is particularly suitable as the catalyst used in the process according to the present invention.
The amount of the catalyst in carrying out the process according to the present invention is 0.1 to 20 % by weight, preferably 0.5 to 10 % by weight of the amount of the raw material.
In carrying out the process according to the present invention, the compound (I) is mixed with the solid acid catalyst, if necessary the solvent is also mixed and the mixture is heated under agitation at 50 to 300"C, preferably 100 to 200"C, for one minute to 2 hours, preferably for 2 min to one hour.
After the reaction is over, the catalyst is able to be removed from the reaction mixture only by filtration. It is an important feature of the process according to the present invention that the removal of the catalyst from the reaction mixture is extremely easy.
The present invention will be explained in detail while referring to the non-limitative Examples and Comparative Examples as follows.
EXAMPLE 1:
Into 10.7 ml of xylene, 1.072 g (7.87 mmol) of 2-phenyl-2-propanol were dissolved, and while stirring and heating the solution at 140"C, 10.7 mg of aluminum silicate (made by SOEKAWA
RIKAGAKU Co., Ltd., Al203.3SiO2) were added to the solution, and the mixture was reacted as it was for 20 min.
On examining the reaction mixture by thin layer chromatography (on silica gel made by Merck, HPTLC 5628, with an eluant of a mixed solvent hexane/ethyl acetate=200/1), the raw material, 2-phenyl-2-propanol, had completely disappeared and only a-methylstyrene was formed without any formation of cyclized dimer. According to the examination of the reaction product by gaschromatography with 2-acetonaphthone as the internal standard, the amount of the thus formed a-methylstyrene was 0.879 g (7.44 mmol, a yield of 94.5 %).
COMPARATIVE EXAMPLE 1:
Into 10.4 ml of xylene, 1.041 g (7.64 mmol) of 2-phenyl-2-propanol were dissolved, and while stirring and heating the solution at 140"C, 0.1 ml of concentrated sulfuric acid was added to the solution, and the mixture was reacted as it was for 10 min.
On examining the reaction mixture by thin layer chromatography, it was found that the raw material, 2-phenyl-2-propanol had completely disappeared, a compound with a polarity of a little higher than that of a-methylstyrene had been mainly formed and a-methylstyrene had scarcely been formed.
A part of the main product isolated from the reaction mixture by column-chromatography was presumed to be the following cyclized dimer from the results of nuclear magnetic resonance spectrum and mass spectrum runs, i.e. formula Ill wherein Ar' is 1,2-phenylene and R is CH3.
a-value on NMR (250 MHz, in CDCI3)
1.36 (3H,s)
1.40 (3H,s)
2.02 (3H,s)
2.24 (1H,d)
2.36 (1H,d)
7.0 to 7.4 (9H,m)
Mass spectral data (DI, 70 eV) m/e: 236 and 221
EXAMPLE 2:
A mixture of 253.4 mg (1.36 mmol) of 2-(2-naphthyl)-2-propanol and 2.5 ml of xylene was heated at 140"C under agitation, and 2.5 mg of aluminum silicate (the same as in Example 1) were added to the mixture in which a part of the raw material had been undissolved, and the whole mixture was reacted for 15 min. After cooling the reaction mixture, aluminum silicate was removed therefrom by filtration and the solvent was distilled off from the filtrate.The residue was subjected to purification by column-chromatography (the column being Merck LOBARB-B, and the eluant being a 200:1 mixture of hexane and ethyl acetate) to obtain 213.6 mg (1.27 mmol) of pure 2-isopropenylnaphthalene in a yield of 93.3 %.
COMPARATIVE EXAMPLE 2:
A mixture of 113.4 mg (0.609 mmol) of 2-(2-naphthyl)-2-propanol and 1 ml of xylene was heated at 140"C under agitation, and while stirring the mixture, 0.02 ml of concentration sulfuric acid was added to the mixture, and the whole mixture was reacted for 10 min as it was. As a result of examining the reaction product by thin layer chromatography, it was found that although the raw material, 2-(2-naphthyl)-2-propanol had completely disappeared from the reaction mixture, 2-isopropenylnaphthalene was scarcely recognized therein and the cyclized dimer was the main product. By purifying the reaction product by the same column-chromatography as in
Example 2, 93.5 mg (0.278 mmol) of the following cyclized dimer were obtained in a yield of 91.3 %, i.e. formula Ill wherein Ar' is 2,3-naphthalene and R is CH3.
value on NMR (250 MHz, in CDCI3) 1.38 (3H,s)
1.42 (3H,s)
2.05 (3H,s)
2.32 (1H,d)
2.44 (1H,d)
7.0 to 7.9 (13H, m)
Mass spectral data (DI, 70 eV) m/e : 336 and 321
EXAMPLE 3:
A mixture of 112.7 mg (0.605 mmol) of 2-(2-naphthyl)-2-propanol and 1 ml of xylene was heated at 110"C under agitation, and 11.2 mg of H-type zeolite (made by TOYO Soda Co., Ltd.,
Mark: TSZ-330HSA) were added to the mixture. The whole mixture was reacted for 10 min. On
examining the reaction mixture by gas-chromatography while using 2,6-diisopropylnaphthalene as
the internal standard, it was found that 92.3 mg (0.549 mmol) of 2-isopropenylnaphthalene were
formed in a yield of 90.7 %.It was also found by examining the reaction mixture through thin
layer chromatography and gas-chromatography that the raw material had disappeared completely
from the reaction mixture.
COMPARATIVE EXAMPLE 3:
A mixture of 99.0 mg (0.532 mmol) of 2-(2-naphthyl)-2-propanol and 1 ml of toluene was
heated at 110 C under agitation, and 8.0 mg of another H-type zeolite (made by TOYO Soda
Co., Ltd., Mark: TSZ-330 HUA) were added to the mixture. The whole mixture was reacted for
10 min.
On examining the reaction mixture by gas-chromatography while using 2,6-diisopropylnaphthal
ene as the internal standard, it was found that 43.2 mg (0.257 mmol) of 2-isopropenyinaphthal- ene were formed in a yield of 45.1 %. According to the examination by thin layer chromato
graphy and gas-chromatography on the reaction mixture, the raw material had completely disap
peared from the reaction mixture and according to the result of thin layer chromatography of the
reaction mixture, the cyclized dimer was another product of the reaction.
In this connection, the difference of activity between the two H-type zeolites, TSZ-330HSA
and TSZ-330HUA, depends on the difference between their Brónsted acid quantities, and the
specific surface area of H-type zeolite TSZ-330HSA is the same as that of H-type zeolite TSZ
330HUA. Namely, since it has been known that TSZ-330 HSA has the Brdnsted acid points 2
times of number of those of TSZ-330HUA, it has been confirmed that Brdnsted acid is the
source of the high selectivity of vinyl compounds in the present invention.
EXAMPLE 4:
After mixing 27.6 mg of the same aluminum silicate in Example 1 and 2.8 ml of xylene and
heating the mixture at 1400C while agitating, 276.3 mg (2.26 mmol) of 1-phenylethanol were
dropped into mixture, and the whole mixture was reacted as it was for 30 min.
On examining the reaction mixture by gas-chromatography with a-methylstyrene as the internal
standard and thin layer chromatography, it was found that the raw material had disappeared
completely from the reaction mixture and that 217 mg (2.08 mmol) of styrene had been formed
in a yield of 92. 1 % without any formation of cyclized dimer.
EXAMPLE 5:
Into a three-necked flask of a capacity of 300 ml provided with a stirrer, a gas inlet tube and
a reflux condenser, 10.0 g (58.7 mmol) of 2-isopropylnaphthalene and 100 g of an aqueous 30
% solution of sodium hydroxide were introduced and while heating the thus introduced sub
stances at 85"C, molecular oxygen was blown into the flask at a rate of 4.0 litres/hour while
stirring vigorously the content of the flask at 500 r.p.m. The reaction was stopped after 8
hours, and after cooling the content of the flask was taken out therefrom and extracted three
times with each 100 ml of ethyl acetate. The ethyl acetate layers were collected, washed with
an aqueous 5 % solution of hydrogen chloride and then with an aqueous saturated solution of
sodium chloride, and then dried with anhydrous sodium sulfate.By distilling off ethyl acetate
from the thus dried product, 10.5 g of a pale yellow oil was obtained.
On examining the composition of the thus obtained oil by gas-chromatography while using
hexamethylbenzene as the internal standard, the oil contained 5.2 g (30.5 mmol, a reaction rate
of 48.0 %) of 2-isopropylnaphthalene, 4.5 g (24.2 mmol, a yield of 41.1 % and a selectivity of
85.6 %) of 2-(2-naphthyl)-2-propanol and 0.33 g (1.94 mmol), a yield of 3.3 % and a selectivity
of 6.9 %) of 2-acetonaphthone.
While heating the whole of the above-mentioned oil at 140"C, each 100 mg of the same
aluminum silicate as in Example 1 was carefully added to the oil three times. After heating and
stirring the oil mixture for 30 min and then cooling thereof, the catalyst (aluminum silicate) was
filtered off, and the filtrate was analyzed by gas-chromatography to find that 3.71 g (22.1 mmol)
of 2-isopropenylnaphthalene were formed.
In addition, according to a separate experiment, crystals of 2-isopropenylnaphthalene can be
easily isolated from a mixture of 2-isopropylnaphthalene and 2-isopropenylnaphthalene by recrys
tallization of the mixture from hexane or,methanol.
Further, according to the actual measurement, 2-isopropylnaphthalene boils respectively at
118, 129 and 143"C under a reduced pressure of 5, 10 and 20 mmHg, and 2-isopropenylna
phthalene boils respectively at 129, 138 and 154"C under a reduced pressure of 5, 10 and 20
mmHg. Accordingly, separation of 2-isopropenylnaphthalene from 2-isopropylnaphthalene can be
easily effected by distillation under a reduced pressure.
Claims (18)
1. A process for preparing an aromatic vinyl compound of the formula
wherein Ar is phenyl, 1 -naphthyl or 2-naphthyl and R is H or methyl, which comprises the liquidphase dehydration, by heating, of an aromatic alcohol of the formula
wherein Ar and R are as defined above, in the presence of a solid acid catalyst.
2. A process according to claim 1, wherein the solid acid catalyst is aluminium silicate.
3. A process according to claim 1, wherein the solid acid catalyst is an H-type synthetic zeolite.
4. A process according to any preceding claim, wherein the amount of the solid acid catalyst is 0.1 to 20% by weight of the amount of the aromatic alcohol.
5. A process according to claim 4, wherein the amount of the solid acid catalyst is 0.5 to 10% by weight of the amount of the aromatic alcohol.
6. A process according to any preceding claim, which is conducted in the presence of a solvent.
7. A process according to claim 6, wherein the solvent is hexane, heptane, benzene, toluene or xylene.
8. A process according to claim 6, wherein the solvent is the aromatic hydrocarbon from which the aromatic alcohol has been produced.
9. A process according to claim 8, wherein the solvent is 2-isopropylnaphthalene.
10. A process according to any of claims 6 to 9, wherein the solvent has a boiling point higher than that of the aromatic vinyl compound.
11. A process according to claim 10, wherein the solvent is 2-isopropylnaphthalene, 2,6diisopropylnaphthalene, 2,7-diisopropylnaphthalene or a mixture of 2,6-diisopropylnaphthalene and 2,7-diisopropylnaphthalene.
12. A process according to any of claims 6 to 11, wherein the amount of the solvent is 0.5 to 20 times by volume of the weight of the aromatic alcohol.
13. A process according to claim 12, wherein the amount of the solvent is 1 to 10 times by volume of the weight of the aromatic alcohol.
14. A process according to any preceding claim, which is conducted at 50 to 3000C.
15. A process according to claim 14, which is conducted at 100 to 200 C.
16. A process according to any preceding claim, which is conducted for from 1 min to 2 hours.
17. A process according to claim 16, which is conducted for from 2 min to 1 hour.
18. A process according to claim 1, substantially as described in any of the Examples.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60135790A JPS61293936A (en) | 1985-06-21 | 1985-06-21 | Liquid-phase dehydration of alcohol having aromatic side-chain at alpha-site |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8614739D0 GB8614739D0 (en) | 1986-07-23 |
| GB2176801A true GB2176801A (en) | 1987-01-07 |
Family
ID=15159894
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08614739A Withdrawn GB2176801A (en) | 1985-06-21 | 1986-06-17 | Liquid-phase dehydration of aromatic alcohols |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS61293936A (en) |
| DE (1) | DE3620512A1 (en) |
| FR (1) | FR2585016A1 (en) |
| GB (1) | GB2176801A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999042425A1 (en) * | 1998-02-18 | 1999-08-26 | Shell Internationale Research Maatschappij B.V. | Process for the preparation of styrenes |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5603711B2 (en) * | 2009-09-02 | 2014-10-08 | 東ソー・ファインケム株式会社 | Diethyl zinc composition, method for thermal stabilization of diethyl zinc, compound for improving thermal stability of diethyl zinc |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB626362A (en) * | 1945-07-13 | 1949-07-13 | Koppers Co Inc | Improvements relating to the production of vinyl naphthalene |
| GB668763A (en) * | 1950-01-04 | 1952-03-19 | Dow Chemical Co | Improvements in or relating to the production of nuclear substituted alkenyl aromatic compounds and boric acid esters thereof |
| GB1126783A (en) * | 1965-06-28 | 1968-09-11 | Halcon International Inc | Co-production of a styrene and a diolefin |
| GB1133313A (en) * | 1964-01-07 | 1968-11-13 | Halcon International Inc | Production of styrenes and of oxirane compounds |
| GB1269420A (en) * | 1968-08-05 | 1972-04-06 | Halcon International Inc | Production of aralkenes |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1583091A (en) * | 1976-05-10 | 1981-01-21 | Exxon Research Engineering Co | Process for the manufacture of styrene |
| JPS5936892B2 (en) * | 1977-01-07 | 1984-09-06 | 三井東圧化学株式会社 | Method for recovering useful substances from cumene process phenol distillation residue |
| DE2736948C3 (en) * | 1977-08-17 | 1981-12-03 | The Dow Chemical Co., 48640 Midland, Mich. | Process for the preparation of a monovinylidene aromatic monomer by dehydration |
| JPS55102521A (en) * | 1979-01-31 | 1980-08-05 | Sumitomo Chem Co Ltd | Improved method for preparation of styrene |
| US4255599A (en) * | 1980-03-12 | 1981-03-10 | Gulf Research & Development Company | Preparation of styrene from ethylbenzene |
| JPS5944291B2 (en) * | 1982-09-03 | 1984-10-29 | 株式会社東芝 | Method for producing trifluoromethylstyrene derivative |
| JPS6172727A (en) * | 1984-09-17 | 1986-04-14 | Nippon Sheet Glass Co Ltd | Production of styrene |
-
1985
- 1985-06-21 JP JP60135790A patent/JPS61293936A/en active Pending
-
1986
- 1986-06-17 GB GB08614739A patent/GB2176801A/en not_active Withdrawn
- 1986-06-19 DE DE19863620512 patent/DE3620512A1/en not_active Ceased
- 1986-06-20 FR FR8608962A patent/FR2585016A1/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB626362A (en) * | 1945-07-13 | 1949-07-13 | Koppers Co Inc | Improvements relating to the production of vinyl naphthalene |
| GB668763A (en) * | 1950-01-04 | 1952-03-19 | Dow Chemical Co | Improvements in or relating to the production of nuclear substituted alkenyl aromatic compounds and boric acid esters thereof |
| GB1133313A (en) * | 1964-01-07 | 1968-11-13 | Halcon International Inc | Production of styrenes and of oxirane compounds |
| GB1126783A (en) * | 1965-06-28 | 1968-09-11 | Halcon International Inc | Co-production of a styrene and a diolefin |
| GB1269420A (en) * | 1968-08-05 | 1972-04-06 | Halcon International Inc | Production of aralkenes |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999042425A1 (en) * | 1998-02-18 | 1999-08-26 | Shell Internationale Research Maatschappij B.V. | Process for the preparation of styrenes |
| US6395946B1 (en) | 1998-02-18 | 2002-05-28 | Shell Oil Company | Process for the preparation of styrenes |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61293936A (en) | 1986-12-24 |
| DE3620512A1 (en) | 1987-01-02 |
| GB8614739D0 (en) | 1986-07-23 |
| FR2585016A1 (en) | 1987-01-23 |
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|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |