CA2290959A1 - Continuous method for reducing carbonyl compounds - Google Patents
Continuous method for reducing carbonyl compounds Download PDFInfo
- Publication number
- CA2290959A1 CA2290959A1 CA002290959A CA2290959A CA2290959A1 CA 2290959 A1 CA2290959 A1 CA 2290959A1 CA 002290959 A CA002290959 A CA 002290959A CA 2290959 A CA2290959 A CA 2290959A CA 2290959 A1 CA2290959 A1 CA 2290959A1
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- CA
- Canada
- Prior art keywords
- process according
- catalyst
- ketones
- reduction
- general formula
- 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.)
- Abandoned
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/24—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with substituted hydrocarbon radicals attached to ring carbon atoms
- C07D213/28—Radicals substituted by singly-bound oxygen or sulphur atoms
- C07D213/30—Oxygen atoms
-
- 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
- C07C1/207—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms from carbonyl compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/35—Preparation of halogenated hydrocarbons by reactions not affecting the number of carbon or of halogen atoms in the reaction
-
- 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
- C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
- C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
- C07C29/14—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group
-
- 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
- C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
- C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
- C07C29/143—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of ketones
-
- 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
- C07C2521/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Pyridine Compounds (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a continuous method for producing primary or secondary alcohols by reducing the corresponding aldehydes or ketones with a secondary aliphatic alcohol as the hydrogen donor, in the presence of a catalyst. The reduction takes place in the gas phase and an amorphous partially dehydrated zirconium hydroxide is used as the catalyst. The inventive method is also suitable for the selective reduction of .alpha.,.beta.-unsaturated aldehydes and ketones. If the reduction is carried out at higher temperatures, the corresponding olefins can be obtained directly from ketones through the dehydration of the resulting secondary alcohols.
Description
,' CA 02290959 1999-11-25 Continuous process for the reduction of carbonyl compounds The present invention relates to a continuous process for the reduction of aldehydes and ketones by means of a secondary alcohol as a hydrogen donor in the presence of a heterogeneous catalyst.
The reduction of aldehydes and ketones to the corresponding primary or secondary alcohols by means of secondary alcohols such as, for example, isopropyl alcohol as a hydrogen donor in the presence of catalysts ("Meerwein-Ponndorf-Verley reduction") is a standard reaction of organic chemistry. The reaction is customarily carried out batchwise in the liquid phase using soluble catalysts such as, for example, aluminium alkoxides. It is also known that Meerwein-Ponndorf-Verley reductions can be carried out under heterogeneous catalysis (C. F. de Graauw et al., Synthesis, 1994, 1007-1017). Because of the easier working-up of the reaction mixture and the reuse of the catalyst which is possible under certain circumstances, this variant is of industrial interest. Even these heterogeneously catalysed reactions, however, were mostly carried out in solution and batchwise. For use on an industrial scale, on the other hand, batchwise ("batch") processes in general are unfavourable. One study dealt with continuous reductions over magnesium oxide (J. Kijenski et al., J. Chem. Soc. Perkin Trans. 2, 1991, 1695-1698), but only poor to moderate yields were obtained there, in particular in the reduction of aryl alkyl ketones, and relatively high reaction temperatures were necessary.
The object of the present invention was therefore to make available a continuous process for the reduction of aldehydes and ketones, which affords good yields even with not very reactive substrates such as, for example, p-chloroacetophenone and does not require high reaction temperatures.
According to the invention, this object is achieved by the process according to Patent Claim 1.
The reduction of aldehydes and ketones to the corresponding primary or secondary alcohols by means of secondary alcohols such as, for example, isopropyl alcohol as a hydrogen donor in the presence of catalysts ("Meerwein-Ponndorf-Verley reduction") is a standard reaction of organic chemistry. The reaction is customarily carried out batchwise in the liquid phase using soluble catalysts such as, for example, aluminium alkoxides. It is also known that Meerwein-Ponndorf-Verley reductions can be carried out under heterogeneous catalysis (C. F. de Graauw et al., Synthesis, 1994, 1007-1017). Because of the easier working-up of the reaction mixture and the reuse of the catalyst which is possible under certain circumstances, this variant is of industrial interest. Even these heterogeneously catalysed reactions, however, were mostly carried out in solution and batchwise. For use on an industrial scale, on the other hand, batchwise ("batch") processes in general are unfavourable. One study dealt with continuous reductions over magnesium oxide (J. Kijenski et al., J. Chem. Soc. Perkin Trans. 2, 1991, 1695-1698), but only poor to moderate yields were obtained there, in particular in the reduction of aryl alkyl ketones, and relatively high reaction temperatures were necessary.
The object of the present invention was therefore to make available a continuous process for the reduction of aldehydes and ketones, which affords good yields even with not very reactive substrates such as, for example, p-chloroacetophenone and does not require high reaction temperatures.
According to the invention, this object is achieved by the process according to Patent Claim 1.
It has been found that on use of amorphous partially dehydrated zirconium hydroxide (ZrO2~xH20) as a catalyst and a secondary aliphatic alcohol as a hydrogen donor, aldehydes and ketones can be reduced continuously in the gas phase to the corresponding primary and secondary alcohols in good yield. In order to obtain the amorphous state of the catalyst, the reaction temperature here must be below the crystallization temperature of the amorphous zirconium (hydr)oxide of typically about 400-500°C.
The secondary aliphatic alcohol employed is preferably isopropyl alcohol.
The process according to the invention is also suitable for the selective reduction of oc,~3-unsaturated carbonyl compounds such as, for example, cinnam aldehyde, 2-hexenal or senecioaldehyde. The C-C double bond is not attacked here.
The use of the process according to the invention is also preferred for the reduction of aryl alkyl and heteroaryl alkyl ketones of the general formula RZ r~
R
in which R1 is an optionally substituted aromatic or heteroaromatic radical and RZ is hydrogen or a C1_6-alkyl group. Aromatic radicals are, for example, phenyl, naphthyl, biphenylyl, anthryl or phenanthryl, hetero-romatic radicals are, for example, pyridyl, quinolyl, pyrryl, indolyl, furyl or thienyl. Substituents of R1 are fundamentally all groups which are neither removed nor modified under the reaction conditions, i.e., for example, C1_6-alkyl groups, halogens or C1_6-alkoxy groups.
Of these, those ketones are particularly preferred in which R1 is an optionally substituted phenyl or pyridyl group.
The secondary aliphatic alcohol employed is preferably isopropyl alcohol.
The process according to the invention is also suitable for the selective reduction of oc,~3-unsaturated carbonyl compounds such as, for example, cinnam aldehyde, 2-hexenal or senecioaldehyde. The C-C double bond is not attacked here.
The use of the process according to the invention is also preferred for the reduction of aryl alkyl and heteroaryl alkyl ketones of the general formula RZ r~
R
in which R1 is an optionally substituted aromatic or heteroaromatic radical and RZ is hydrogen or a C1_6-alkyl group. Aromatic radicals are, for example, phenyl, naphthyl, biphenylyl, anthryl or phenanthryl, hetero-romatic radicals are, for example, pyridyl, quinolyl, pyrryl, indolyl, furyl or thienyl. Substituents of R1 are fundamentally all groups which are neither removed nor modified under the reaction conditions, i.e., for example, C1_6-alkyl groups, halogens or C1_6-alkoxy groups.
Of these, those ketones are particularly preferred in which R1 is an optionally substituted phenyl or pyridyl group.
In one variant of the process according to the invention, the reduction of the aryl alkyl or heteroaryl alkyl ketones (I) is carried out at a temperature of 250-350°C, so that the initially formed secondary alcohol of the general formula OH
R~ xI
is dehydrated in situ to give the corresponding olefin of the general formula ru, in which R1 and RZ have the meanings mentioned under (I) .
The following examples clarify the implementa-tion of the process according to the invention, without a restriction being seen therein.
Example 1 Preparation of amorphous partially dehydrated zirconium hydroxide 50 kg of zirconyl chloride solution (265 g/1, calculated as Zr02) were semicontinuously precipitated with sodium hydroxide solution (300) in the course of 5 h in a flow-through reactor equipped with a high speed stirrer (Ultra-Turrax~, 9000 min-1). The sodium hydroxide solution was added by means of a metering pump at such a rate that the precipitation took place at a constant pH of 8Ø As less than the stoichiometric amount of NaOH was needed for this, the remainder of the stoichiometric amount was added to the resulting zirconium hydroxide suspension after the precipitation. The suspension was then dewatered in a chamber filter press and the filter cake was washed with deionized water until neutral and chloride-free.
The washed filter cake was dried at 100°C and then introduced into water, the pieces of filter cake breaking into small parts. These were again dried at 100°C and then heated to 300°C at 30 K/h and calcined at this temperature for 8 h. The product thus obtained was amorphous to X-ray amorphous, and had a specific surface area according to BET of 196 mz/g and a pore volume of 0.43 cm3/g.
Example 2 1-Phenylethanol from acetophenone 5.0 g of catalyst (from Example 1) having a particle size of 0.315-1.0 mm were packed into a tubular reactor having a diameter of 13 mm. The reactor was heated to 160°C. After reaching this temperature, the reactor was supplied with 10.5 g/h of a solution of 5~ acetophenone in isopropyl alcohol, 100 ml/min of nitrogen being used as a carrier gas. After leaving the reactor, the gaseous reaction mixture was cooled to 5°C
and the condensate was analysed by gas chromatography.
Yield (GC): 960.
Example 3 Styrene from acetophenone The procedure was as described in Example 2, but the reaction temperature was 290°C and the carrier gas flow was 25 ml/min.
Yield (GC): 93~.
Example 4 1-Phenylpropanol from propiophenone Analogously to Example 2, propiophenone was employed instead of acetophenone at a reaction temperature of 150°C. The carrier gas flow was 50 ml/min.
Yield (GC): 95%.
Example 5 1-Phenyl-1-propene from propiophenone Analogously to Example 3, propiophenone was employed instead of acetophenone at a reaction temperature of 300°C. The carrier gas flow was 50 ml/min.
Yield (GC): 940 (74~ trans-1-phenyl-1-propene, 20o cis-1-phenyl-1-propene).
Example 6 1-(4-Chlorophenyl)ethanol from p-chloroacetophenone Analogously to Example 2, p-chloroacetophenone was employed instead of acetophenone at a reaction temperature of 150°C. The carrier gas flow was 100 ml/min.
Yield (GC): 96.5.
Example 7 p-Chlorostyrene from p-chloroacetophenone Analogously to Example 3, p-chloroacetophenone was employed instead of acetophenone at a reaction temperature of 290°C. The carrier gas flow was 100 ml/min.
Yield (GC): 95.1.
Example 8 1-(3-Pyridyl)ethanol from 3-acetylpyridine Analogously to Example 2, 3-acetylpyridine was employed instead of acetophenone at a reaction temperature of 220°C. The carrier gas flow was - 50 ml/min.
Yield (GC): 96.9.
Example 9 3-Vinylpyridine from 3-acetylpyridine Analogously to Example 3, 3-acetylpyridine was employed instead of acetophenone at a reaction temperature of 320°C. The carrier gas flow was 50 ml/min.
Yield (GC): 85.5%.
R~ xI
is dehydrated in situ to give the corresponding olefin of the general formula ru, in which R1 and RZ have the meanings mentioned under (I) .
The following examples clarify the implementa-tion of the process according to the invention, without a restriction being seen therein.
Example 1 Preparation of amorphous partially dehydrated zirconium hydroxide 50 kg of zirconyl chloride solution (265 g/1, calculated as Zr02) were semicontinuously precipitated with sodium hydroxide solution (300) in the course of 5 h in a flow-through reactor equipped with a high speed stirrer (Ultra-Turrax~, 9000 min-1). The sodium hydroxide solution was added by means of a metering pump at such a rate that the precipitation took place at a constant pH of 8Ø As less than the stoichiometric amount of NaOH was needed for this, the remainder of the stoichiometric amount was added to the resulting zirconium hydroxide suspension after the precipitation. The suspension was then dewatered in a chamber filter press and the filter cake was washed with deionized water until neutral and chloride-free.
The washed filter cake was dried at 100°C and then introduced into water, the pieces of filter cake breaking into small parts. These were again dried at 100°C and then heated to 300°C at 30 K/h and calcined at this temperature for 8 h. The product thus obtained was amorphous to X-ray amorphous, and had a specific surface area according to BET of 196 mz/g and a pore volume of 0.43 cm3/g.
Example 2 1-Phenylethanol from acetophenone 5.0 g of catalyst (from Example 1) having a particle size of 0.315-1.0 mm were packed into a tubular reactor having a diameter of 13 mm. The reactor was heated to 160°C. After reaching this temperature, the reactor was supplied with 10.5 g/h of a solution of 5~ acetophenone in isopropyl alcohol, 100 ml/min of nitrogen being used as a carrier gas. After leaving the reactor, the gaseous reaction mixture was cooled to 5°C
and the condensate was analysed by gas chromatography.
Yield (GC): 960.
Example 3 Styrene from acetophenone The procedure was as described in Example 2, but the reaction temperature was 290°C and the carrier gas flow was 25 ml/min.
Yield (GC): 93~.
Example 4 1-Phenylpropanol from propiophenone Analogously to Example 2, propiophenone was employed instead of acetophenone at a reaction temperature of 150°C. The carrier gas flow was 50 ml/min.
Yield (GC): 95%.
Example 5 1-Phenyl-1-propene from propiophenone Analogously to Example 3, propiophenone was employed instead of acetophenone at a reaction temperature of 300°C. The carrier gas flow was 50 ml/min.
Yield (GC): 940 (74~ trans-1-phenyl-1-propene, 20o cis-1-phenyl-1-propene).
Example 6 1-(4-Chlorophenyl)ethanol from p-chloroacetophenone Analogously to Example 2, p-chloroacetophenone was employed instead of acetophenone at a reaction temperature of 150°C. The carrier gas flow was 100 ml/min.
Yield (GC): 96.5.
Example 7 p-Chlorostyrene from p-chloroacetophenone Analogously to Example 3, p-chloroacetophenone was employed instead of acetophenone at a reaction temperature of 290°C. The carrier gas flow was 100 ml/min.
Yield (GC): 95.1.
Example 8 1-(3-Pyridyl)ethanol from 3-acetylpyridine Analogously to Example 2, 3-acetylpyridine was employed instead of acetophenone at a reaction temperature of 220°C. The carrier gas flow was - 50 ml/min.
Yield (GC): 96.9.
Example 9 3-Vinylpyridine from 3-acetylpyridine Analogously to Example 3, 3-acetylpyridine was employed instead of acetophenone at a reaction temperature of 320°C. The carrier gas flow was 50 ml/min.
Yield (GC): 85.5%.
Example 10 3-Methyl-2-buten-1-of from 3-methylcrotonaldehyde Analogously to Example 2, 3-methylcroton-aldehyde (senecioaldehyde) was employed instead of acetophenone at a reaction temperature of 140°C. The carrier gas flow was 25 ml/min.
Yield (GC): 77.1%
Yield (GC): 77.1%
Claims (6)
1. Process for the preparation of primary or secondary alcohols by reduction of the corresponding aldehydes or ketones using a secondary aliphatic alcohol as a hydrogen donor in the presence of a catalyst, characterized in that the reaction is carried out continuously in the gas phase over an amorphous partially dehydrated zirconium hydroxide as a catalyst at a temperature below the crystallization temperature of the catalyst.
2. Process according to Claim 1, characterized in that the secondary aliphatic alcohol employed is isopropyl alcohol.
3. Process according to Claim 1 or 2, characterized in that the aldehyde or ketone employed is an .alpha.,.beta.-unsaturated carbonyl compound.
4. Process according to Claim 1 or 2, characterized in that the ketone employed is a ketone of the general formula in which R1 is an optionally substituted aromatic or heteroaromatic radical and R2 is hydrogen or a C1-6-alkyl group.
5. Process according to Claim 4, characterized in that R1 is an optionally substituted phenyl or pyridyl group.
6. Process according to Claim 4 or 5, characterized in that the reaction is carried out at a temperature of 250-350°C and the initially formed secondary alcohol of the general formula is dehydrated in situ to give the corresponding olefin of the general formula in which R1 and R2 have the abovementioned meanings.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH1414/97 | 1997-06-11 | ||
| CH141497 | 1997-06-11 | ||
| PCT/EP1998/003091 WO1998056743A1 (en) | 1997-06-11 | 1998-05-26 | Continuous method for reducing carbonyl compounds |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2290959A1 true CA2290959A1 (en) | 1998-12-17 |
Family
ID=4209893
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002290959A Abandoned CA2290959A1 (en) | 1997-06-11 | 1998-05-26 | Continuous method for reducing carbonyl compounds |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0988266A1 (en) |
| JP (1) | JP2002513420A (en) |
| AU (1) | AU8535098A (en) |
| CA (1) | CA2290959A1 (en) |
| WO (1) | WO1998056743A1 (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2482207A (en) * | 1946-07-09 | 1949-09-20 | Carbide & Carbon Chem Corp | Process for making styrene and substituted styrenes |
| JPS61204143A (en) * | 1986-09-10 | 1986-09-10 | Japan Tobacco Inc | Method of reducing aldehyde and ketone |
| CZ54498A3 (en) * | 1997-03-07 | 1998-11-11 | Lonza Ag | Catalyst mixture based on amorphous, particularly dehydrated zirconium oxide hydroxide, process of its preparation and use |
-
1998
- 1998-05-26 AU AU85350/98A patent/AU8535098A/en not_active Abandoned
- 1998-05-26 EP EP98936284A patent/EP0988266A1/en not_active Withdrawn
- 1998-05-26 CA CA002290959A patent/CA2290959A1/en not_active Abandoned
- 1998-05-26 WO PCT/EP1998/003091 patent/WO1998056743A1/en not_active Application Discontinuation
- 1998-05-26 JP JP50142399A patent/JP2002513420A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| EP0988266A1 (en) | 2000-03-29 |
| JP2002513420A (en) | 2002-05-08 |
| AU8535098A (en) | 1998-12-30 |
| WO1998056743A1 (en) | 1998-12-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |