JPS647980B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a norbornyl-2-aldehyde having an unsaturated hydrocarbon side chain and a method for producing the same. Compounds in which an aldehyde group is bonded to a norbornene ring include compounds with an unsaturated bond in the norbornane ring, such as Diels-Alder reaction adducts of acrolein and cyclopentadiene, as disclosed in U.S. Pat. No. 3,748,344. It is known what it has. However, as in the present invention,
Norbornyl-2- with an unsaturated hydrocarbon side chain
Aldehydes are unknown. As a result of intensive research aimed at synthesizing a new norbornyl aldehyde having an unsaturated hydrocarbon side chain such as a vinyl group or an ethylidene group, the present inventors found that
This completes the present invention. The norbornyl-2-aldehyde having an unsaturated hydrocarbon side chain according to the present invention has a wide range of uses as a raw material for fragrances, an organic synthesis reagent, a raw material for polymers, and the like. That is, the present invention relates to norbornyl-2-aldehyde having an unsaturated hydrocarbon side chain and represented by the following general formula (), and a method for producing the same. In the above formula, C ₂ is a vinyl group or an ethylidene group, which is bonded to the 5 or 6 position of the norbornane ring, and the dotted line indicates a single bond when C ₂ is a vinyl group, and a double bond when it is an ethylidene group. and R ₁ and R ₂ each represent a hydrogen atom or a methyl group (the same applies hereinafter in the present specification). Norbornyl-2 represented by the above formula
-As the aldehyde, 5 or 6-vinyl-norbornyl-2 represented by the following general formula ()
-aldehyde, 5- or 6-ethylidenenorbornyl-2-aldehyde, and the like. Furthermore, as the compound of the general formula (),
5 or 6-vinyl-3 represented by the following formula
-methyl-norbornyl-2-aldehyde, 5- or 6-ethylidene-3-methyl-norbornyl-2-aldehyde, and the like. Next, to explain the production of norbornyl-2-aldehyde of the present invention, one method is to hydrolyze a glycidic acid ester represented by the following general formula () and then decarboxylate it at 50 to 250°C. . In the above formula, the definitions of C ₂ , the dotted line, R ₁ and R ₂ are the same as in the above general formula (), and R ₃ represents a hydrocarbon group having 1 to 6 carbon atoms. Hydrolysis is carried out in an acidic or basic aqueous solution, but decomposition is usually faster in a basic environment, and it is preferable to use a mixture of water and alcohol, such as ethanol, as the solvent. As the base, metal hydroxides such as sodium hydroxide and potassium hydroxide, and metal alcoholates such as sodium methylate are used. The temperature during hydrolysis is 0 to 100°C. When hydrolyzed with basicity, glycidic acid is obtained in the form of a salt. Next, a mineral acid such as hydrochloric acid is added to acidify it to give glycidic acid, and then 50~
Decarboxylate by heating to 250°C. reaction temperature is 50
If the temperature is lower than 250℃, the decarboxylation reaction will be difficult to proceed.
If the temperature is higher than ℃, decomposition reactions other than decarboxylation and polymerization reactions are likely to occur. A more preferable decarboxylation temperature is 60 to 150°C. The heating time should be continued until the generation of carbon dioxide gas stops, but usually
It takes about 0.5 to 5 hours. After heating, the product is separated from the reaction mixture by an appropriate means such as extraction or distillation, and then repurified to obtain the norbornyl-2-aldehyde of the present invention. The glycidic acid ester represented by the above general formula () has the following general formula: norbornanone and monohalogenoacetate, such as alkyl monobromoacetate,
It can be produced by reacting an alkyl monohalogenoacetate such as an alkyl monochloroacetate in the presence of a basic catalyst to perform dehydrohalogenation. Here, the alkyl group in the alkyl monohalogenoacetate includes methyl, ethyl, propyl, isopropyl, butyl, sec-butyl,
Examples include amyl, isoamyl, hexyl, 2-ethylbutyl, and cyclohexyl groups. In addition, in the above dehydrohalogenation, if the number of carbon atoms in the alkyl group of the monohalogenoacetic ester is 1
- 6, the reaction is completed relatively quickly, and as a result, the hydrolysis and subsequent decarboxylation of the obtained glycidic acid ester are easy;
When the number of carbon atoms in the alkyl group is 7 or more, reactions such as dehydrohalogenation, hydrolysis and decarboxylation take too much time and are also disadvantageous from an economical point of view. Therefore, it is preferable to use an alkyl monohalogenoacetate having an alkyl group having 1 to 6 carbon atoms. Industrially advantageous are methyl monochloroacetate, ethyl monochloroacetate, isopropyl monochloroacetate and ethylene glycol monochloroacetic diester. Next, as another manufacturing method, the following general formula ()
In this method, 2-norbornene represented by the formula (2) is reacted with carbon monoxide and hydrogen at 30 to 300°C in the presence of a catalyst to obtain norbornyl-2-aldehyde of the formula (). As the compound of the above general formula (), 5-vinyl-norbornene-2, 5 or 6-vinyl-3
-Methyl-norbornene-2,5-ethylidene-
Norbornene-2, 5 or 6-ethylidene-3
-Methyl-norbornene-2, etc. This reaction is expressed as follows. The reaction products include compounds in which an aldehyde group is introduced at the 2-position of the norbornane ring, as shown in (') in the above reaction formula, as well as compounds in which an aldehyde group is bonded at the 3-position, and C ₂ , that is, vinyl. A compound in which a group or an ethylidene group is hydroformylated, and a compound in which a hydroformylated compound is further condensed can be obtained. For this purpose, the catalyst must be selected so as to maximize the yield of the norbornyl-2-aldehyde of general formula (') above, which is the object of the present invention. From a large number of experimental results, in order to achieve the above reaction, transition metal compounds are used as catalysts,
It has been found that compounds of Group 8 elements in the periodic table are particularly useful. Among Group 8 metal compounds, metal compounds such as cobalt, rhodium, iridium, ruthenium, or platinum are useful, and of course, in the case of complexes of these metal compounds such as metal carbonyl compounds, the selection of the reaction It is important to know what kind of ligand to coordinate in order to improve the efficiency.
The electron donating properties and steric size of the ligand must be fully considered. Some of these metal carbonyls are commercially available, such as cobalt carbonyl (mp51-52°C, decomposed), but they can also be prepared before use by reacting active metal powders or other metal compounds with carbon monoxide. You can also do that. In order to enhance the effect, the following compounds can be coordinated with these carbonyl complexes, or they can be used as catalysts by making them coexist in the reaction system. Examples of such ligands include tertiary amines and phosphites. In particular, addition complexes of alkyl tertiary phosphines such as tributylphosphine and triphenylphosphine are effective in hydroformylation reactions. On the other hand, although it may have a negative catalytic effect in some cases, it is generally very useful for increasing the selectivity of the target product of the present invention. Among the metal compounds, cobalt compounds and rhodium compounds are preferred, and these may be used alone or with the addition of other metal compounds as promoters. Regarding the reaction conditions when the above metal compound is used, the reaction temperature is in the range of 30 to 300°C, more preferably 50 to 250°C. The pressure is usually 1~
Selected within the range of 450Kg/ ^cm2 . The molar ratio of carbon monoxide/hydrogen fed into the reaction system can be varied from 1:1 to 1:4 depending on the yield of the reaction product, but is usually about 1:1.
That's fine. In addition, the hydroformylation reaction is generally carried out in a liquid phase using a solvent, and the solvents include saturated hydrocarbons, aromatics such as benzene, ethers,
Alcohols, esters, sulfolane, water, and the reaction product itself can be used alone or in mixtures of two or more. In a typical hydroformylation reaction method, 2-norbornene is charged into a pressurized reaction vessel together with carbon monoxide, hydrogen and a solvent, and the reaction is carried out by heating to a predetermined temperature in the presence of a catalyst. After the reaction is complete, unreacted carbon monoxide and hydrogen are removed, the catalyst is separated or decomposed by an appropriate method, and the reaction product is then treated by precision distillation etc. to produce the target norbornyl aldehyde. obtain. The present invention will be explained in detail with reference to Examples below. Reference example 1 (glycidic acid ester) 5 or 6-vinyl-2-norbornanone 0.15
t containing 0.15 mol of potassium t-butoxide in a mixture of 0.15 mol of potassium t-butoxide and 0.15 mol of ethyl monochloroacetate.
- After adding 200 ml of butanol solution and reacting at 20°C for 3 hours, the reaction mixture was poured into water, extracted with ether, and the ether extract was distilled under reduced pressure to obtain a glycide of the following formula with a yield of 62%. A mixture of acid esters (-1) and (-2) was obtained. The analysis results are as follows. Boiling point: 105-110℃/1.8mmHg IR (liquid film method, cm ^-1 ): 3050, 2930, 2870, 1725, 1660, 1120 nmr (in CDCl ₃ ): 6.3-5.4δ (multiplet, 1H) 5.2- 4.7δ (multiplet, 2H) 4.5~4.0δ (quadruplet, 2H) 3.8~3.6δ (triplet, 1H) 2.9~1.1δ (multiplet, 12H) Elemental analysis value (C ₁₃ H ₁₈ O ₃ ): C (%) H (%) Calculated value 70.2 8.2 Analytical value 70.1 8.2 Reference example 2 Using 5- or 6-ethylidene-2-norbornanone as the starting material, the reaction was carried out in the same manner as in Reference example 1 to produce the following formula. Glycidic acid ester (-3) and (
A mixture of -4) was obtained with a yield of 85%. The analytical values were as follows. Boiling point: 119-122℃/1.8mmHg ir (cm ^-1 ): 3090, 2935, 2870, 1725, 1120 nmr: 5.6-5.1δ (multiplet, 1H) 4.5-4.1δ (quadruplet, 2H) 3.8- 3.6δ (triplet, 1H) 2.7~1.0δ (multiplet, 14H) Elemental analysis value (as C ₁₃ H ₁₈ O ₃ ): C (%) H (%) Calculated value 70.2 8.2 Analysis value 70.2 8.2 Example 1 [5- or 6-vinyl-norbornyl-2-aldehyde] 2.5 g (0.011 mol) of the mixture of glycidic acid esters (-1) and (-2) of the following formula obtained in Reference Example 1, Dissolved in 10 ml of 99.5% ethanol, added 2.5 g of 28% methanol solution of sodium methylate at below 20°C, then added 0.3 ml of water, heated to about 70°C and stirred for 3 hours to dissolve the above glycidic acid ester. was hydrolyzed. Next, add 1.2 ml of concentrated hydrochloric acid and 5.7 ml of water to this mixture.
was added and heated under reflux for 3 hours to perform decarboxylation.
After the reaction was completed, the solvent was neutralized, washed with water, dried, and the solvent was distilled off under reduced pressure to obtain 0.9 g of 5- or 6-vinyl-norbornyl-2-aldehyde (yield:
54.5%). The boiling point was 67°C/3.0mmHg. Analysis result ir: C-H stretching vibration of vinyl group at 3050cm ^-1 , 1630cm
^-1 also shows the C=C stretching vibration of the vinyl group, and 2730 cm ^-1 shows the C-H stretching vibration of the aldehyde group,
At 1725 cm ^-1 , C=O stretching vibrations of the aldehyde group are also shown. nmr: 0.3τ (singlet, 1H) 4.1τ (multiplet, 1H) 4.8τ (multiplet, 2H) 6.5-9.0τ (multiplet, 10H) Elemental analysis (as C ₁₀ H ₁₄ O): C (% ) H (%) Calculated value 80.0 9.3 Actual value 79.8 9.4 Example 2 [5 or 6-ethylidene-norbornyl-2
-aldehyde] Glycidic acid ester obtained in Reference Example 2 (
-3) and (-4) mixture 10.0g (0.044 mol)
of, It was dissolved in 50 ml of 99.5% ethanol, and hydrolyzed and decarboxylated in the same manner as in Example 1 to obtain 3.2 g (yield: 48%) of the title 5- or 6-ethylidene-norbornyl-2-aldehyde. Boiling point is 84-87
It was ℃/10mmHg. Analysis result ir: C-H stretching vibration of aldehyde group at 2710 cm ^-1 ,
The same C=O stretching vibration of the aldehyde group is shown at 1725 cm ^-1 , the C-H stretching vibration of the ethylidene group is shown at 3009 cm ^-1 , and the C=O stretching vibration of the ethylidene group is also shown at 1665 cm ^-1 .
C stretching vibrations are shown respectively. nmr: 0.3τ (singlet, 1H) 4.4-4.8τ (multiplet, 1H) 8.4τ (doublet, 3H) 6.5-9.1τ (multiplet, 9H) Elemental analysis (as C ₁₀ H ₁₄ O) C (%) H (%) Calculated value 80.0 9.3 Actual value 79.7 9.1 Example 3 [3-methyl-5 or 6-vinyl-norbornyl-2-aldehyde] The following formula was used instead of the glycidic acid ester mixture as the raw material in Example 1. glycidic acid ester mixture of
The same operation was carried out using 0.011 mol. The desired title 3-methyl-5 or 6-vinyl-norbornyl-2-aldehyde was obtained in a yield of 52.5%. The boiling point was 55-56°C/2.0mmHg. Analysis result ir: C-H stretching vibration of vinyl group at 3050cm ^-1 , 1630cm
^-1 shows C=C stretching vibration of vinyl group, 2730cm ^-1
shows the C-H stretching vibration of the aldehyde group, and the C=O stretching vibration of the aldehyde group is shown at 1725 cm ^-1 . nmr: 0.3τ (singlet, 1H) 4.1τ (multiplet, 1H) 4.8τ (multiplet, 2H) 6.5~9.0τ (multiplet, 9H) 9.1τ (doublet, 3H) Elemental analysis (C ₁₁ As H ₁₆ O) C (%) H (%) Calculated value 80.5 9.8 Actual value 80.2 9.5 Example 4 [3,3-dimethyl-5 or 6-vinyl-norbornyl-2-aldehyde] Glyside as the raw material in Example 1 Instead of the acid ester mixture, a glycidic acid ester mixture of the formula
The same operation was carried out using 0.011 mol. The desired title 3,3-dimethyl-5 or 6-vinyl-norbornyl-2-aldehyde
Obtained with a yield of 67.8%. Boiling point is 65-67℃/2.0mmHg
It is. Analysis result ir: C-H stretching vibration of vinyl group at 3050cm ^-1 , 1630cm
^-1 shows the C=C stretching vibration of the vinyl group, 2730 cm ^-1 shows the C-H stretching vibration of the aldehyde group, and 1725 cm ^-1 shows the C=O stretching vibration of the aldehyde group. nmr: 0.3τ (singlet, 1H) 4.2τ (multiplet, 1H) 4.8τ (multiplet, 2H) 6.5~9.0τ (multiplet, 8H) 9.0τ (doublet, 6H) Elemental analysis (C ₁₂ As H ₁₈ O) C (%) H (%) Calculated value 80.9 10.1 Actual value 81.3 9.9 Example 5 [3-Methyl-5 or 6-ethylidene-norbornyl-2-aldehyde] Glycidic acid ester as raw material in Example 2 Instead of the mixture, a glycidic acid ester mixture of the following formula
The same operation was carried out using 0.044 mol. 56.8 of the desired title 3-methyl-5 or 6-ethylidene-norbornyl-2-aldehyde.
% yield. The boiling point was 90-92°C/12mmHg. Analysis result ir: C-H stretching vibration of ethylidene group at 3050 cm ^-1 ,
C=C stretching vibration of ethylidene group is shown at 1675 cm ^-1 , C-H stretching vibration of aldehyde group is shown at 2725 cm ^-1 ,
The C=O stretching vibration of the aldehyde group is shown at 1730 cm ^-1 . nmr: 0.5τ (singlet, 1H) 4.6τ (multiplet, 1H) 6.6~8.9τ (multiplet, 8H) 8.5τ (doublet, 3H) 9.1τ (doublet, 3H) Elemental analysis (C ₁₁ H ₁₆ O) C (%) H (%) Calculated value 80.5 9.8 Actual value 80.4 9.7 Example 6 [3,3-dimethyl-5 or 6-ethyldene-norbornyl-2-aldehyde] Of the raw materials in Example 2 Instead of the glycidic acid ester mixture, a glycidic acid ester mixture of the following formula
The same operation was carried out using 0.044 mol. As a result, the title 3,3-dimethyl-5 or 6-ethylidene-norbornyl-2-aldehyde was obtained in a yield of 60.3%. Boiling point is 66-69℃/3mmHg
It was hot. Analysis result ir: C-H stretching vibration of ethylidene group at 3050 cm ^-1 ,
C=C stretching vibration of ethylidene group at 1675cm ^-1 , 2725
C-H stretching vibration of aldehyde group in cm ^-1 , 1730 cm ^-1
shows the C=O stretching vibration of the aldehyde group. nmr: 0.5τ (singlet, 1H) 4.5τ (multiplet, 1H) 6.7~9.0τ (multiplet, 7H) 8.5τ (doublet, 3H) 8.9τ (doublet, 6H) Elemental analysis (C ₁₂ H ₁₈ O) C (%) H (%) Calculated value 80.9 10.1 Actual value 81.1 9.8 Examples 7 to 15 In Examples 7 to 15 shown below, this reaction was carried out by a hydroformylation reaction using carbon monoxide and hydrogen. Norbornyl-2 with an unsaturated hydrocarbon side chain of the invention
-Produced aldehydes. That is, put norbornene, methylnorbornene, reaction solvent, and catalyst shown in the table below into a pressure cooker with an internal volume of 500 ml, and pressurize synthesis gas (CO/H ₂ = 1:1), and react at the pressure, temperature, and time shown in the table below. After cooling, excess unreacted gas was removed. After treating the contents of the autoclave with oxygen and hydrochloric acid to remove the catalyst, the organic layer was separated, washed with water, and dried. First, the solution was recovered, and then the residue was distilled under reduced pressure. The obtained fraction was fractionated twice by vacuum precision distillation, and then the main fraction was compared with the analysis results of the compounds obtained in Examples 1 to 6 by IR and NMR spectroscopy and elemental analysis. The structure was confirmed and the yield was determined. The results are summarized in the table below.

【table】

[Table] In the above table, catalysts with a uniform appearance were mainly used; however, in Example 12, a chlorrhodium carbonyl complex RhCl(CO) ₂ P(C ₆ H ₅ ) Approximately the same results were obtained when 15 mmol of 10% of ₂ was deposited on silica powder. It has been found that the yield (ie, selectivity) of the target product generally improves when a complex salt is attached with a phosphine ligand. In addition, in Example 11, cobalt carbonyl
Cobalt hydrocarbonyl instead of _Co2 (CO) ₈
Almost the same results were obtained using HCo(CO) ₄ , and in Example 14, rhodium carbonyl _Rh4
Almost the same results were obtained when rhodium carbonylacetylacetonate was used in place of (CO) ₁₂ . Furthermore, in Example 9, palladium hydroxide Pd(OH) ₂ and nickel carbonyl Ni were used as catalysts.
(CO) ₄ , nickel acetylacetonate Ni
(C ₅ H ₇ O) ₂ , iron carbonyl Fe(CO) ₅ , etc., the yield of the target product is 2 to 12%, and in the end, considering the results of other examples, the period Among the Group 8 metal compounds in the Table of Contents, cobalt compounds and rhodium compounds were found to be the most effective, followed by iridium, ruthenium, and the like.

Claims (1)

[Scope of Claims] 1. A norbornyl-2-aldehyde having an unsaturated hydrocarbon side chain and represented by the following general formula (). In the formula, C ₂ is a vinyl group or an ethylidene group, which is bonded to the 5 or 6 position of the norbornane ring, and the dotted line indicates a single bond when C ₂ is a vinyl group, and a double bond when it is an ethylidene group. and R ₁ and R ₂ each represent a hydrogen atom or a methyl group. 2. The norbornyl-2-aldehyde according to claim 1, wherein the compound of the general formula () is represented by the following general formula (). 3. A norbornyl compound represented by the following general formula () having an unsaturated hydrocarbon side chain, which is characterized by hydrolyzing a glycidic acid ester represented by the following general formula () and then decarboxylating it at 50 to 250°C. Method for producing 2-aldehyde. In both formulas, C ₂ is a vinyl group or an ethylidene group, and is bonded to the 5 or 6 position of the norbornane ring, and the dotted line indicates a single bond when C ₂ is a vinyl group, and a double bond when it is an ethylidene group. R ₁ and R ₂ are a hydrogen atom or a methyl group, and R ₃ is a hydrocarbon group having 1 to 6 carbon atoms. 4 The glycidic acid ester of the above general formula () is represented by the following formula (), and the above general formula ()
The norbornyl-2-aldehyde of is represented by the following formula ()
A method for producing norbornyl-2-aldehyde according to claim 3. 5 2-norbornene, carbon monoxide, and hydrogen represented by the following general formula () are the 8th group in the periodic table.
Nobornyl-2 represented by the following general formula (') having an unsaturated hydrocarbon side chain, characterized in that it is reacted at 30 to 300°C in the presence of a group element compound.
-Production method of aldehyde. In both formulas, C ₂ is a vinyl group or ethylidene group and is bonded to the 5 or 6 position of the norbornane ring or norbornene ring, and the dotted line indicates a single bond when C ₂ is a vinyl group, and indicates a single bond when C 2 is an ethylidene group. Each represents a double bond, and R ₁ represents a hydrogen atom or a methyl group. 6 The compound of the general formula () is 5-vinyl-2
-norbornene or 5-ethylidene-2-norbornene, and the compound of the general formula (') is represented by the following formula ().
2. The method for producing norbornyl-2-aldehyde as described in 2. 7. The method for producing norbornyl-2-aldehyde according to claim 5, wherein the Group 8 element compound is a compound of cobalt, rhodium, iridium, ruthenium, or platinum.