GB2108953A - Process for the preparation of a chloropropyl compound - Google Patents
Process for the preparation of a chloropropyl compound Download PDFInfo
- Publication number
- GB2108953A GB2108953A GB08132629A GB8132629A GB2108953A GB 2108953 A GB2108953 A GB 2108953A GB 08132629 A GB08132629 A GB 08132629A GB 8132629 A GB8132629 A GB 8132629A GB 2108953 A GB2108953 A GB 2108953A
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- GB
- United Kingdom
- Prior art keywords
- compound
- catalyst
- chloroallyl
- palladium
- hydrogenated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/09—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrolysis
- C07C29/12—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrolysis of esters of mineral acids
- C07C29/124—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrolysis of esters of mineral acids of halides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/44—Palladium
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/09—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrolysis
- C07C29/095—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrolysis of esters of organic acids
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/17—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrogenation of carbon-to-carbon double or triple bonds
- C07C29/172—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by hydrogenation of carbon-to-carbon double or triple bonds with the obtention of a fully saturated alcohol
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/10—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with ester groups or with a carbon-halogen bond
- C07C67/11—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with ester groups or with a carbon-halogen bond being mineral ester groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/28—Preparation of carboxylic acid esters by modifying the hydroxylic moiety of the ester, such modification not being an introduction of an ester group
- C07C67/283—Preparation of carboxylic acid esters by modifying the hydroxylic moiety of the ester, such modification not being an introduction of an ester group by hydrogenation of unsaturated carbon-to-carbon bonds
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
3-Chloropropyl alcohol or an acylate thereof is prepared by hydrogenating the corresponding 3- chloroallyl compound using a palladium catalyst, at a pressure of at most 15 bar, preferably at ambient temperature and pressure in a non- polar solvent.
Description
SPECIFICATION
Process for the preparation of a chloropropyl compound
This invention relates to a process for the preparation of a 3-chloropropyl compound, Cl(CH2)3X, by contacting a 3-chloroallyl compound, CICH=CHCH2X, with hydrogen in the presence of a Group 8 metal catalyst.
From German Offenlegungsschrift 2.436.602 it is known that 3-chloroallyl alcohol, i.e. X=OH, can be hydrogenated using a rhodium catalyst to 3-chloropropanol, albeit with a yield of 6%. From the same document it is known, that the acetate derived from this alcohol, i.e. X=OCOCH3, may be hydrogenated too, using a Group 8 metal-in particular rhodium-at a temperature of about 500C and a pressure of about 50 bar.
It has now been found that the 3-chloroallyl compounds CICH=CHCH2X, wherein X=OH or OOCR (R=H, alkyl), can be hydrogenated at low pressures, when using palladium as the catalyst.
The invention therefore provides a process for the preparation of a 3-chloropropyl compound,
Cl(CH2)3X, by contacting a 3-chloroallyl compound, CICH=CHCH2X, with hydrogen in the presence of a
Group 8 metal catalyst, characterized in that a 3-chloroallyl hydroxide or carboxylate is hydrogenated at a pressure of at most 1 5 bar using palladium as the catalyst.
The process according to the invention affords conversions of the 3-chloroallyl compound of up to 100%, with selectivities towards the 3-chloropropyl compound of up to 72%. It should be borne in mind that hydrogenation of the olafinic bond always occurs simultaneously with some hydrogenolysis of the chloroallyl compound, thus yielding a n-propyl compound in addition to the 3-chloropropyl compound.
The advantages of the inventive process are that the process can be carried out at low pressure, even at 1 bar (atmospheric pressure), and also at ambient temperature, while giving high yields of hydrogenated products.
The 3-chloroallyl compound CICH=CHCH2X may be an hydroxide (X=OH) or a carboxylate (X=OOCR, R=H, alkyl). The compounds wherein X=OH or OOCCH3 are preferred because of their ready availability and their good results in the hydrogenation according to the invention. The alkyl group R need not be larger than 10 C atoms. If the substituent X is an halogen, e.g. Cl, hydrogenation does not occur under the inventive conditions.
The starting material, e.g. the compound with X=OH, 3-chloro-2-propen-1 -ol, is readily available from 1 3-dichloropropene, by reaction with aqueous Na2CO3 at about 800 C. A mixture of approximately equal amounts of cis and trans 1,3-dichloropropene is the major waste product of the allylchloride preparation by the high temperature chlorination of propene, and is not a very valuable chemical substance.The process according to the invention thus provides a commercially attractive route from 1 3-dichloropropene via 3-chloro-2-propen-1 -ol to more interesting compounds such as trimethylene glycol (1 ,3-propanediol). Trimethylene glycol is an important fine chemical, which is traditionally manufactured from acrolein, but which may be prepared now by hydrolysis of 3-chloropropanol, obtained from 3-chloropropenol. The application also relates therefore to a process for the preparation of 1 ,3-propanediol, which includes the process according to the invention for the hydrogenation of a 3-chloroallyl hydroxide or carboxylate.
The hydrogenation is carried out preferably in the liquid phase, in particular in solution. More preferably the hydrogenation is carried out with the 3-chloroallyl compound dissolved in a non-polar solvent. It appears that polar and protic solvents like water or alcohols have a deleterious effect on the selectivity. The presence of moisture in the catalyst should also be avoided, preferably, for also in that case the main hydrogenation product may be the dehalogenated product C3H,X. Advantageously therefore the palladium catalyst is substantially dried before use.
The nonpolar solvent may be an organic liquid having a low dielectric constant, i.e. below 0.5
Debije. Examples are carbon tetrachloride, pentane, hexane, heptane, dioxane, octane, isooctane, cyclohexane, benzene, toluene and other aromatics, ketones such as methyl isobutylketone and methylethyl ketone, and ethers such as diisopropylether. Preferably the nonpolar solvent is cyclohexane or octane.
As said, the hydrogenation is carried out at a low pressure of at most 1 5 bar. Preferably the 3chloroallyl compound is hydrogenated at a pressure in the range from 1 to 10 bar. In particular the pressure may be 1 bar, which obviously is advantageous because the use of pressure vessels and related equipment is obviated and the hydrogen gas may simply be bubbled through the reaction mixture.
The reaction temperature may be raised, but this is not necessary: preferably the 3-chloroallyl compound is hydrogenated at a temperature in the range from 0 to 400 C. When working in a certain solvent, the reaction temperature should not be higher than its boiling point or lower than its freezing point. For instance, when using benzene, the temperature should not be below 60C. It is particularly advantageous to work at room temperature, i.e. in the range of 1 8 to 250C. The temperature may rise somewhat due to the exothermic nature of the reaction.
The palladium may be used in homogeneous form, i.e. powderous or in wires, but preferably the palladium is dispersed on a porous carrier, such as silica or calcium carbonate, and in particular alumina or carbon. The carbon may be a charcoal, a coke or a similar product, preferably an activated coai powder.
Good results are obtained also when a minor proportion of platinum is added to the palladium catalyst. A minor proportion means here that the resultant catalyst should contain more palladium than platinum by weight. Catalysts containing exclusively Pt are too selective towards hydrogenolysis yielding too much of the n-propyl compound.
Satisfactory catalysts contain from 4 to 10 %w Pd on carbon or alumina, to which from 0 to 2 %w Pt may have been added.
The following Examples illustrate the invention. All percentages are by weight, unless indicated otherwise. Analyses are by NMR and gas-liquid chromatography (GLC).
Example 1
Preparation of 3-chloro-2-propen-l -ol from 1.3-dichloropropene 1,3-Dichloropropene containing 1 5-20% 1,2-dichloropropane was obtained commercially and used as received. It consisted of a mixture of cis (45%) and trans (55%) isomer.
A mixture of crude 1,3-dichloropropene (100 ml; containing 0.86 mol), sodium carbonate (125 g; 1.1 8 mol) and water (1000 ml) was heated under reflux for 6 hours. GLC analysis indicated that the 1,3-dichloropropene was completely converted to give 3-chloro-2-propen-1 -ol (cis/trans mixture) as the sole product. The mixture was then cooled to ambient temperature. The 3-chloro-2-propen-1-ol product was extracted with ether and the ether solution dried and evaporated and the residue distilled to yield 65 g (82%) of pure 3-chloro-2-propen-1 -ol, b.p. 145-1 550C. The boiling points of the cis and trans isomers are 146 and 1 540 C, respectively.
Example 2
Hydrogenation of 3-chloro-2-propen-1-ol (CPE)
A mixture of CPE (25 g) in cyclohexane (255 ml) was hydrogenated over a 10% Pd/C catalyst (0.5 g) at 250C and 5 bar. GLC analysis after 24 hours indicated complete conversion of CPE to give 58 %m 3-chloropropan-1-ol and 42 %m n-propanol. The solution was filtered to remove the catalyst and subjected to fractional distillation to give pure 3-chloropropan-1 -ol, b.p. 1 60-1 620C.
Example 3
Conversion of 3-chloropropan-1 -ol to 1.3-propanediol A solution of 3-chloropropen-1-ol (117 g; 1.23 mol) and sodium carbonate (144 g; 1.36 mol) in water (250 ml) was heated at 950C for 4 hours. The mixture was filtered to remove undissolved salts and the water evaporated in a rotary evaporator. The slurry which remained was diluted with 300 ml absolute ethanol. Salts were filtered off and the filtrate evaporated to leave 91.2 g (98%) 1,3-propanediol which was pure according to GLC and NMR analysis.
Example 4
Preparation of 3-chloroallylacetate from 1,3-dichloropropene A mixture of crude 1,3-dichloropropene (200 ml), sodium acetate (266 g) and water (800 ml) was heated under reflux for 3 hours. The organic phase was separated and distilled under vacuum to give a product which contained 82% 3-chloroallylacetate and 15% 3-chloro-2-propen-1 -ol.
Example 5
Hydrogenation of 3-chloroal lylacetate (CAA)
A 20 %w solution of CAA in ethyl acetate was hydrogenated over a 10% Pd/C catalyst (1 %w on
CAA) at 250C and 1 bar. After 22 hours the conversion of CAA was 86% and 3-chloropropylacetate and propyl acetate were formed in 40 and 60% selectivity, respectively. Vacuum distillation of the product afforded pure 3-chloropropylacetate. This ester can be hydrolysed to 1,3-propanediol according to the procedure of Example 3.
Example 6
Influence of catalyst and solvent
The experiment of Example 2 was repeated using various different catalysts and solvents.
Experiments A to G are comparative, while experiments H to K are according to the invention. In all experiments the intake consists of 10 %w 3-chloro-2-propen-1 -ol (based on the solvent) and 2 %w catalyst (based on the chloropropenol), whereas the reaction time is 24 hours. The results are given in
Table I. It is apparent that catalysts containing Pd (Experiments H, I, J, K) combine a 100% conversion with a moderate (Experiments H and I) or a high (Experiments J and K) selectivity towards the desired 3-chloroaliylalcohol (3-chloropropan-1 -ol). Experiments I and K differ only in the polarity of the solvent, showing that apolar solvents do raise the selectivity. Experiment D also shows a good selectivity, but the conversion is a mere 4%, whereas Experiment A shows a good conversion with an extremely poor selectivity. Finally, Experiments F and G prove, that the presence of a non-polar solvent alone (in the absence of palladium) is not enough: both the conversion and the selectivity are poor.
Table I
Selectivity (% molar)
Chloropropenol 3-chloro
Temp. Pressure conversion propan
Experiment Catalyst Solvent ( C) (bar) (%) 1-ol 1-propanol
A 5% Pt/C ethanol 80 10 100 6 94
B 5% Pt/Ca ethanol 25 7 37 7 93
C 5% Pt/Ca ethanol 25 7 13 5 95
D 5% Ru/Ca ethanol 25 7 4 60 40
E 5% Rh/Ca ethanol 25 7 25 28 72
F 5% Rh/Al2O3 cyclohexane 100 10 50 complex mixture
G 5% Pt/C cyclohexane 25 1 < 5 -
H 5% Pd/Ca ethanol 25 7 100 29 71
I 4% Pd, ethanol 25 7 100 30 70 1% Pt/Ca
J 10% Pd/C cyclohexane 25 5 100 58 42
K 4% Pd, cyclohexane 25 7 100 64 36 1% Pt/Cb a) These catalysts were obtained from Degussa (trade name) and contained 50-60% water.
b) The catalyst was dried by azeotropic removal of water with cyclohexane prior to use.
Example 7
Influence of solvent
Using the same intake ratios and conditions as in Example 6, several experiments were carried out to investigate the influence of different solvents. Unless otherwise stated the 3-chloro-2-propen-1 ol conversion was 100%. The results are given in Table II.
Table II Selectivity (% molar)
Pressure 3-chloro
Experiment Catalyst Solvent Temp. ( C) (bar) propan-l-ol 1-propanol
L 10% Pd/C cyclohexane 25 1 52a 48a
M 10% Pd/C cyclohexane 25 5 58 42
N 10% Pd/C cyclohexane 100 10 48 52
0 10% Pd/C ethanol 25 1 42 58
P 10% Pd/C dioxane 25 1 48 52
Q 10% Pd/C dioxane 25 1 39 61
(+NaOH)
R 10% Pd/C dioxane 25 1 60 40
(+HCI)
S 10% Pd/C acetic acid 25 1 73b 27C
T 10% Pd/ dioxane 25 1 53 47 CaCO3 U 10% Pd/ ethanol 25 1 42 58
CaCO3
a) 87% chloropropenol conversion
b) 3-chloropropylacetate C) n-propylacetate
The Experiments L, M and N show the behaviour at different reaction temperatures and pressures; apparently the best yields are obtained at 250C and 5 bar when using cyclohexane as the solvent. Experiments 0 and U show that ethanol, a protic solvent, is detrimental to the chloropropanol selectivity: both times 42% I Experiments P, Q and R are interesting in that they show that HCl in dioxane raises the chloropropanol selectivity, whereas NaOH in dioxane lowers it, pure dioxane being intermediate.
Example 8
Hydrogenation of 3-chloroallylacetate
The experiment of Example 5 was repeated with various catalysts. In all experiments a 20 %w solution of 3-chloroallylacetate in ethylacetate was hydrogenated for 22 hours at 250C and 1 bar, using 1 %w of catalyst (based on the 3-chloroallylacetate). The results are given in Table Ill.
Table lil
Selectivity (% molar)
Conversion
Experiment Catalyst { /0) Cl(CH2)3OAc CH3(CH2)2OAc V 5% Pd/AI203 52 44 56
W 10% Pd/C 86 40 60
X 10% Pd/CaCO3 82 44 56
Y 5% Pt/C < 5
Z 5% Rh/AI203 < 5
Experiments Y and Z are not according to the invention since the catalysts employed do not contain palladium, and it is apparent that these catalysts are inactive under the experimental conditions.
Example 9
Influence of carrier material
Four different carrier materials were compared using cyclohexane as solvent in the hydrogenation of 3-chloro-2-propen-1-ol. The conditions were equal to those of Example 2, except that 20 %w of 3chloro-2-propen-1-ol (based on the solvents was used and that the pressure was 1 bar. The results are given in Table IV.
Table IV
Selectivity (% molar)
Conversion 3-chloro
Experiment Catalyst { /0) propanol 1-propanol
AA 10% Pd/C 100 52 48 BB 5% Pd/AI203 100 71 29
CC 10% Pd/CaCO3 36 72 28
DD 5% Pd/SiO2 52 62 38
EE 5% Pd/SiO2a 72 57 43
a) catalyst activated prior to use by contacting with a H2 gas stream during 24 hours.
Apparently the best combination of selectivity and conversion is obtained using a 5% Pd on alumina catalyst (Experiment BB).
Claims (13)
1. Process for the preparation of a 3-chloropropyl compound, Cl(CH2)3X, by contacting a 3chloroallyl compound, CICH=CHCH2X, with hydrogen in the presence of a Group 8 metal catalyst, characterized in that a 3-chloroallyl hydroxide or carboxylate is hydrogenated at a pressure of at most 1 5 bar using palladium as the catalyst.
2. A process as claimed in claim 1, characterized in that the hydrogenation is carried out with the 3-chloroallyl compound dissolved in a nonpolar solvent.
3. A process as claimed in claim 2, characterized in that the nonpolar solvent is cyclohexane.
4. A process as claimed in claim 2, characterized in that the nonpolar solvent is octane.
5. A process as claimed in any one of claims 1 to 4, characterized in that the 3-chloroallyl compound is hydrogenated at a pressure in the range of from 1 to 10 bar.
6. A process as claimed in any one of claims 1 to 5, characterized in that at a temperature in the range from 0 to 400C the 3-chloroallyl compound is hydrogenated.
7. A process as claimed in any one of claims 1 to 6, characterized in that the palladium is dispersed on a porous carrier.
8. A process as claimed in claim 7, characterized in that alumina or carbon is used as the porous carrier.
9. A process as claimed in any one of claims 1 to 8, characterized in that a minor proportion of platinum is added to the palladium catalyst.
10. A process as claimed in any one of claims 1 to 9, characterized in that the palladium catalyst is substantially dried before use.
11. A process for the preparation of 1,3-propanediol which includes a process as claimed in any one of claims 1 to 10.
12. A process as claimed in claim 1, carried out substantially as described hereinbefore with particular reference to the Examples.
13. A 3-chloropropyl hydroxide, halogenide or carboxylate, whenever prepared by a process as claimed in any one of claims 1 to 12.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08132629A GB2108953A (en) | 1981-10-29 | 1981-10-29 | Process for the preparation of a chloropropyl compound |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08132629A GB2108953A (en) | 1981-10-29 | 1981-10-29 | Process for the preparation of a chloropropyl compound |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2108953A true GB2108953A (en) | 1983-05-25 |
Family
ID=10525479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08132629A Withdrawn GB2108953A (en) | 1981-10-29 | 1981-10-29 | Process for the preparation of a chloropropyl compound |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2108953A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1996017683A1 (en) * | 1994-12-09 | 1996-06-13 | Imperial Chemical Industries Plc | Hydrogenation catalyst and process |
| WO1997044302A1 (en) * | 1996-05-24 | 1997-11-27 | The Dow Chemical Company | Process for preparing a c2-6-alkanol containing from two to four hydroxyl groups |
| US5914432A (en) * | 1994-11-28 | 1999-06-22 | The Dow Chemical Company | Hydrogenation of halogenated compounds |
-
1981
- 1981-10-29 GB GB08132629A patent/GB2108953A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5914432A (en) * | 1994-11-28 | 1999-06-22 | The Dow Chemical Company | Hydrogenation of halogenated compounds |
| WO1996017683A1 (en) * | 1994-12-09 | 1996-06-13 | Imperial Chemical Industries Plc | Hydrogenation catalyst and process |
| WO1997044302A1 (en) * | 1996-05-24 | 1997-11-27 | The Dow Chemical Company | Process for preparing a c2-6-alkanol containing from two to four hydroxyl groups |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |