JPS5832841A - Ethylnorbornyl-2-aldehyde and its preparation - Google Patents

Abstract

NEW MATERIAL:The compound of formulaI(C2H5 is bonded to the 5- or 6- position of norbornane ring; R1 and R2 are H or CH3). EXAMPLE:5- or 6-Ethylnorbornyl-2-aldehyde. USE:Raw material of perfumery, reagent for organic syntheses, raw material of polymer, etc. PROCESS:(A) The compound of formulaI(R1 and R2 are especially H) can be prepared by hydrolyzing the compound of formula II (R3 is 1-6C hydrocarbon group; R1 and R2 are especially H), and decarbonating the product at 0-250 deg.C. (B) Another compound of formulaI(R2 is H) can be prepared by reacting the compound of formula III with carbon monoxide and hydrogen in the presence of a catalyst consisting preferably of a compound of a 8-group element of the periodic table, especially a compound of Co, Rh, Ir, Ru or Pt, at 30-300 deg.C. (C) As an alternative method, the compound of formulaIis obtained by the partial hydrogenation of the compound of formula IV[C2 is vinyl (the dotted line is single bond) or ethylidene (the dotted line is double bond)].

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to norbornyl-2-aldehyde having an ethyl group and a method for producing the same.

Examples of compounds in which an aldehyde group is bonded to a norbornane ring include norbornane, such as the Diels-Alder reaction adduct of acrolein and cyclopentanoene, as disclosed in U.S. Patent No. 3, 748.344. Those having an unsaturated bond in the ring are known.

However, norbornyl-2-aldehyde having a 4-ethyl group as in the present invention is not known.

The present inventors completed the present invention as a result of intensive research aimed at synthesizing a novel norbornyl aldehyde having an ethyl group.

That is, the present invention relates to ethylnor-2-aldehyde represented by the following formula (I) and a method for producing the same.

1 In the above formula (1), the ethyl group is 5 or 6 of the norbornane ring.
R1 and R2 are hydrogen atoms or methyl groups.

Representative compounds represented by the formula (I) include:
Examples include 5-ton or 6-nitylnorbornyl-2-aldehyde represented by the following formula (II).

Furthermore, 5 or 6-ethyl-3-methylnorbornyl-
Examples include 2-aldehyde, 5- or 6-ethyl-3,3-zomethylnorbornyl-2-aldehyde.

The ethylnorbornyl-2-aldehyde represented by the formula (I) of the present invention has a wide range of uses, including as a raw material for perfumery, an organic synthesis reagent, and a raw material for polymers.

Next, the method for producing ethylnordernyl-2-aldehyde of the present invention will be explained. One of the methods is to hydrolyze a glycidic acid ester represented by the following formula (It), and then 0 to 2
This method involves decarboxylation at 50°C.

1 In the above formula (■), the definitions of the ethyl group, R1 and .R2 are the same as in the above formula (I), and R3 represents a hydrocarbon group having 1 to 6 carbon atoms.

The above-mentioned glycidic acid ester is hydrolyzed in an acidic or basic aqueous solution, but decomposition is usually faster in a basic solution, and a mixture of water and alcohol, such as ethanol, is preferably used as the solvent. Suitable.As the base, use an alkaline metal hydroxide such as sodium hydroxide or potassium hydroxide, a metal alcoholade or alkaline carbonate such as sodium methylate, or an alkaline ion exchange resin.The temperature for hydrolysis is It is 0-100°C.

When hydrolyzed under basic conditions, glycidic acid is usually obtained in the form of a salt, so it is then acidified by adding a mineral acid such as hydrochloric acid to form glycidic acid, and then decarboxylated at a temperature of 0 to 250°C. Let's do it. When the reaction temperature is lower than 0°C, the decarboxylation reaction is difficult to proceed, and when the reaction temperature is higher than 250°C, decomposition reactions other than decarboxylation and polymerization reactions are likely to occur. More preferably, the decarboxylation temperature is 10 to 150°C. The heating time may be continued until the generation of carbon dioxide gas stops, but is usually about 0.5 to 5 hours. It should be noted that if the hydrocarbon group R3 of the guarinate ester of formula (III) is a hydrocarbon group having more than 6 carbon atoms, this is not preferable because decarboxylation becomes difficult.

After the reaction is completed, the product is separated from the reaction mixture by an appropriate means such as extraction or distillation, and then repurified to obtain ethylnorbornyl-2-aldehyde of the present invention.

The glycidic acid ester represented by the above formula (jII) is prepared by basifying ethylnorbornanone represented by the following general formula and an alkyl monohalogenoacetate such as a monohalogenoacetate, such as an alkyl monobromoacetate or an alkyl monochloroacetate. It can be produced by dehydrohalogenation by reaction in the presence of a catalyst. Here, examples of the alkyl group in monohaloke9anoalkyl acetate include methyl, ethyl, propyl, inzolopyl, butyl, 5ee-butyl, amyl, isoamyl, hexyl, 2-ethylbutyl, and cyclohexyl groups.

In the above dehydrogenation, when the alkyl group of the monohalogenoacetic acid ester has 1 to 6 carbon atoms, the reaction is completed relatively quickly, and as a result, the resulting glycidic acid ester Hydrolysis and subsequent decarboxylation are easy, but when the number of carbon atoms in the alkyl group exceeds 7, reactions such as dehydrohalogenation, hydrolysis, and decarboxylation take too long and are economically difficult. is also disadvantageous.

Therefore, it is preferable to use an alkyl monochloroacetate having an alkyl group having 1 to 6 carbon atoms.

Industrially advantageous monohaloke9noalkyl acetates include methyl monochloroacetate, ethyl monochloroacetate, inzolopyl monochloroacetate, and ethylene glycol monochloroacetic acid diester.

Next, as another method for producing ethylnordernyl-2-aldehyde, ethyl-2-
There is a method of reacting nordelene with carbon monoxide and hydrogen at 30 to 300°C in the presence of a catalyst to obtain an ethylnorbornyl-2-aldehyde group of the following formula.

In both formulas (■) and (2), the ethyl group is bonded to the 5 or 6 position of the norbornene ring or norbornane ring, and R1 represents a hydrogen atom or a methyl group.

Examples of the compound of formula (V) include 5-ethyl-2-norbornene, 5- or 6-ethyl-3-methyl-2-norbornene, and 5-ethyl-3-methyl-2-norbornene. There are runen etc.

This reaction can be expressed as follows.

(■) (White reaction products include compounds in which an aldehyde group is introduced at the 2-position of the norbornane ring, as shown in formula (I') in the above reaction formula, as well as compounds in which an aldehyde group is bonded at the 3-position. For this purpose, the catalyst should be selected so as to maximize the yield of the white norbornyl-2-aldehyde of the above formula, which is the object of the present invention. There must be.

From the results of numerous experiments, it has been found that transition metal compounds are used as catalysts to achieve the above reaction, and compounds of the elements of Group 8 of the Periodic Table are particularly useful.

Among Group 8 metal compounds, cobalt, rhodium,
Metal compounds such as iridium, ruthenium and platinum are useful, and of course, in complexes such as metal-19= compounds, metal compounds such as iridium, ruthenium and platinum can be used to improve the selectivity of the reaction. How the Gantt is coordinated is important, and the electron donating property and steric size of the ligand must be taken into consideration.

Although some cholera metal carbonyls are coated with cobalt carbonyl, they can also be prepared before use by reacting active metal powders or other metal compounds with carbon monoxide. 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 hydriphenylphosphine are effective in hydroformylation reactions. On the other hand, in general, it is of great help in increasing the selectivity of the object of the present invention. Among the metal compounds mentioned above, co-Gult compounds and rhodium compounds rt- are preferred, and these can be used alone or in combination with other metal compounds as co-catalysts.

As the reaction conditions when using the above metal compound, the reaction temperature is in the range of 30 to 300°C, more preferably 50 to 250°C. The reaction pressure is usually 1 to 4
50 to 9/cW1.

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.

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 reaction products. It may be used alone or in a mixture of two or more.

In a typical hydroformylation reaction method, 2-norbornene is charged together with carbon monoxide, hydrogen and a solvent into a pressurized reaction vessel, and the reaction is carried out by heating to a predetermined temperature in the presence of a catalyst. After the reaction is completed, unreacted carbon monoxide and hydrogen are removed, and the catalyst is separated by an appropriate method.
Alternatively, the reaction product is decomposed and then treated by precision distillation to obtain the target norbornyl aldehyde.

The third method for producing ethylnorbornyl-2-aldehyde of the present invention is a method in which nor, represented by the following formula (■), is partially hydrogenated to 2-aldehyde.

1 In the above formula (Vl), C2 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 C2 is a vinyl group, and a double bond when it is an ethylidene group. R1 and R2 are hydrogen atoms or methyl groups, respectively.

Examples of the norbornyl-2-aldehyde represented by the above formula include 5- or 6-vinyl nor-ruer-2-aldehyde represented by the following formula (■), and 5- or 6-ethylidenenorpornyl-2-aldehyde.

Furthermore, as the compound of formula (Vl), 5 or 6
- pinyru-3-methylnorbornyl-2-flutehyde,
5 or 6-ethylidene-3-methylnorbornyl-2
-Aldehydes, etc.

This partial hydrogenation is selectively carried out by partially hydrogenating only the ethylidene group or vinyl group to form an ethyl group without reducing the aldehyde group, and is achieved by catalytic hydrogenation or a reducing reagent.

In the case of catalytic hydrogenation, suitable catalysts include metal elements of group 8 in the periodic table such as palladium, platinum, metals, metals, etc., and their compounds, which can be attached to a carrier such as carbon powder. It may also be used. The reaction pressure ranges from normal pressure to 50 K17 cm, and the reaction temperature ranges from -10 to 200°C.Solvents include alcohols such as ethanol, saturated hydrocarbons such as hexane, aromatic hydrocarbons such as benzene, etc. Esters such as ethyl acetate can be used.

When hydrogenating using a nickel catalyst or partially hydrogenating using a reducing reagent such as soimide,
Nordernyl-2-aldehyde of the above formula (Vl) is replaced with -H
It is convenient to protect the aldehyde group by converting it into an acetal, then hydrogenate it using a nickel catalyst or a reducing reagent such as soimide, and then perform acidic hydrolysis to regenerate the aldehyde group. It is.

In addition, the nor expressed in the above formula (■) is Ruel 2-
The aldehyde can be obtained from ethylidene or vinylnorbornene by a hydroformylation reaction as described above, or by reacting ethylidene or vinylnorbornanone with an alkyl monohalognoacetate as described above to obtain a glycidate ester, followed by hydration. It can also be produced through decomposition and decarboxylation.

Another method for obtaining nyl-2-aldehyde is the Diels-Alder reaction between alkyl clobentacienna and acrolein, but in this case, the Diels-Alder reaction produces extremely diverse by-products. However, the yield of the target product is poor, and it cannot be said to be an industrially advantageous method.

Next, the present invention will be explained in detail with reference to Examples.

Example 1 (54 or 6-nitylnor-2-aldehyde)
A mixture of glycidic acid esters of the formula 2.52 (0,01
Sodium methylate (D 28% J tanner solution 12.5 y'e 2
The mixture was added at 0° C. or lower, and then 0.3 ml of water was added thereto, followed by boiling and stirring for 4 hours for hydrolysis.

Next, add 2 ml of concentrated hydrochloric acid and 6 mef of water to this mixture.
In addition, decarboxylation was performed by stirring at 25-30°C for 3 hours. After completion of the reaction, neutralization, washing with water, drying, distillation of the solvent, and distillation under reduced pressure yielded the title 5-1 i haloethylnorbornyl-2-aldehyde 1, (1 (yield: 6
0%) was obtained. The boiling point was 52-53°C/3.0 Hg.

Analysis result ir: C-H stretching vibration of aldehyde group at 2730 cm-1,
Similarly, C=0 stretching vibration of the aldehyde group is shown at 1725 cm''.

nmr: 0.3τ (doublet, IH) 6.8-9.3τ (multiplet, 15H) 19- Elemental analysis (as C1oH□60): C (ch) H (%) Calculated value 78.9 10 .5 Actual value 78.6 10. '6 Example 2 [3-methyl-5 or 6-ethylnorbornyl-2-
[Anokehyde] Instead of the raw material glycidic acid ester mixture in Example 1, a glycidic acid ester mixture of the following formula was used.
The same procedure was carried out using 0.011 mol.

The desired title 3-methyl-5 or 6-ethylnorbornyl-2-aldehyde was obtained in a yield of 55%. The boiling point was 48-51°C/2.0+mnHg.

-90= Analysis result l r: C-H stretching vibration of aldehyde group at 2730 cm';
The C-0 stretching vibration of the aldehyde group is shown at 1725 cm'.

nmr: 0.3τ (doublet, IH) 6.5-9.0τ (multiplet, 14H) 9.1τ (doublet, 3H) Elemental analysis (as Co HIBO) C (Chi) H (Chi) ) Calculated value ? 9.5 10.8 Actual value? 9.0 10.6 Example 3 (3,3-tmethyl-5 or 6-nitylnorM lunyl-2-aldehyde 9) Instead of the raw material glycidic acid ester mixture in Example 1, a glycidic acid ester mixture of the following formula 0 A similar operation was carried out using .011 mol.

The desired title 3,3-dimethyl-5 or 6-ethylnorbornyl-2-aldehyde was obtained in a yield of 45%. The boiling point is 56-58°C/3.0+mnHg.

Analysis result ir: C-H stretching vibration of aldehyde group at 2730 cm', 17
The C=0 stretching vibration of the aldehyde group is shown at 25 cm-1.

nmr: 0.3τ (-multiplet, IH) 4.2τ (multiplet, IH) 4.8τ (multiplet, 2H) 6.5-9.0τ (multiplet, 13H) 9.07 (multiplet , 6H) Elemental analysis (as C1°H2DO) C (%) H (thi) Calculated value 80.0 11.1 Actual value 79.6 11.0 Example 4 (54; 1u6-nitylnor-2-aldehyde) 5.01 il (o, 03
3 moles), 100ml of ethanol (1.5%) and 0.22% of Lanaumu carbon catalyst were added and sealed (-), then degassing and nitrogen substitution were repeated twice, and then hydrogen gas was fully injected at a pressure of 3Ky/
The mixture was reacted with crl at room temperature for 1 hour. After separating the catalyst from the reaction mixture and recovering ethanol from solution F, the residue was distilled under reduced pressure to obtain 4.6f of 5- or 6-ethylnorpornyl-2-aldehyde (yield: 91cm). Ta.

The physical properties and analytical results of the compound thus obtained were the same as those obtained in Example 1.

Example 5 [3-Methyl-5 or 6-nitylnorpornyl L2-
Aldehyde] In Example 4, 3-methyl-5 or haloethylidene-2-aldehyde was substituted for 5-aldehyde or 6-pinyl-23-lbornyl-2-aldehyde.
The same procedure was carried out except that Of (0,030 mol) was used.

As a result, the desired title compound, 3-methyl-5
'! ;iij 6-ethyl nor is Ruel-2-fur f
Humans were obtained in a yield of 90 cm. The physical properties and analytical results of this compound were the same as those obtained in Example 2.

Examples 6 to 14 In Examples 6 to 14 shown below, the haloethylnordernyl-2-aldehyde of the present invention was produced by a hydroformylation reaction using -carbon oxide and hydrogen.

That is, the raw materials shown in the table below, ethylnorbornene or methylethylnor, are reacted with runene. A solvent and a catalyst are placed in a pressure cooker with an internal volume of 500 cc, and synthesis gas (Co/H
2=1:1) was pressurized and reacted at the pressure, temperature, and time shown in the following table, and then cooled to remove excess unreacted gas. After treating the contents of the pressure cooker with oxygen and hydrochloric acid to remove the catalyst, the organic layer was separated, washed with water, and dried. First, the solvent was recovered, and the residue was distilled under reduced pressure. After the obtained fraction was distilled twice by vacuum precision distillation, the main fraction was
and nmr su-<? By Torr analysis and elemental analysis, and also compared with the analysis results of the compounds obtained in Examples 1 to 5,
The structure was confirmed and the yield was determined. The reaction conditions and results are summarized in the following table.

24- In addition, in the previous work, catalysts were mainly used in the form of catalysts that were almost uniform in appearance during the hydroformylation reaction. Furthermore, as seen in Examples 12 and 14, it was found that the yield (ie, selectivity) of the target product was generally improved when a catalyst attached with a phosphine ligand was used.

In addition, in Example 8, almost the same results were obtained even when the core N"l rutocardenyl Co2 (CO) 8th generation linicobalt hydrocal was used with Nyl HCo (CO)4,
Furthermore, in Example 13, almost the same results were obtained when rhodium carbonylacetylacetonate was used instead of active rhodium hydroxide.

Furthermore, in Example 8, palladium hydroxide Pd(OH)2 was used instead of co-glutocarponyl as a catalyst.
, nickel carbonyl N1(CO)4, nickel acetylacetonate Ni (C5H70)2 s, iron carbonyl Fe (CO) s, etc., it was observed that the yield of the target product decreased. In the end, when the results of other examples were also considered, it was found that the co-Gult compound and the rhodium compound were the most excellent among the metal compounds of Group 8 of the periodic table.

Patent applicant: Japan Petrochemical Co., Ltd.

Claims (1)

[Scope of Claims] (1) Ethylnorbornyl-2-aldehyde represented by the following formula (1), R1...(I) In the formula (■), the ethyl group is It is bonded to the 6-position, and Ro and R2 each represent a hydrogen atom or a methyl group. (2) Ethylnorbornyl according to claim 1, wherein the compound of formula (I) is represented by the following formula (n):
2-aldehyde, formula (n), in which the ethyl group is bonded to the 5 or 6 position of the norbornane ring. (3) Ethylnorbornyl represented by the following formula (1), which is characterized by hydrolyzing the glycidic acid ester represented by the following formula (III) and then decarboxylating it at 0 to 250°C. -2-Aldehyde production method, 1 In both formulas (■) and (1), the ethyl group is bonded to the 5 or 6 position of the norbornane ring, and R1 and R
2 represents a hydrogen atom or a methyl group, and the formula (II
In I), R3 represents a hydrocarbon group having 1 to 6 carbon atoms. (4) The glycidic acid ester of the formula (III) is
Ethylnorbornyl-2-aldehyde represented by the following formula (IV) and wherein the ethylnorbornyl-2-aldehyde of the formula (I) is represented by the following formula (II) Process for producing aldehydes, both formulas (IV) and (1, in which the ethyl group is bonded to the 5 or 6 position of the norbornane ring, and R3 in formula (IV)
represents a hydrocarbon group having 1 to 6 carbon atoms. (5) Ethyl-2-nor M formed by the following formula (V)
) Renene, carbon monoxide and hydrogen in the presence of a catalyst 3
The following formula (which is characterized by reacting at 0 to 300°C)
1') In both formulas (V) and (1'), the ethyl group is bonded to norbornane it or to the 5 or 6 position of the norbornane ring. , R1 represents a hydrogen atom or a methyl group. (6) The method for producing ethylnorbornyl-2-aldehyde according to claim 5, wherein the catalyst is a compound of a Group 8 element of the periodic table. (7) The Group 8 element compound is co-gurt, ronoum,
The method for producing ethylnorbornyl-2-aldehyde according to claim 6, wherein iridium and ruthenium are platinum compounds. 2
- A method for producing ethylnordernyl-2-aldehyde prepared by the following formula (1), characterized by partially hydrogenating the aldehyde, 3-1 In both formulas (Vl) and (I), R1 and R2 are In formula (VI), C2 is a vinyl group or ethylidene group, and is bonded to the 5 or 6 position of the norbornaf term, and the dotted line indicates a single bond when C2 is a vinyl group. , an ethylidene group has a double bond, and the ethyl group in formula (I) is bonded to the 5th or 6th position of the norbornane ring.