JPS6036435A - Production of alpha, beta-unsaturated carbonyl compound - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as perfumery, pharmaceuticals, chemicals, etc., in high yield, by using easily available alkenyl ester and an allyl carbonate compound as raw materials, and heating the materials in the presence of an organotin alkoxide and a catalyst. CONSTITUTION:The objective compound of formula II is produced by heating (A) an alkenyl ester of formula I (R1, R2, R3 and R4 are H or hydrocarbon residue; X is acyl; R1, R2, R3 and R4 may be chains or form a ring at an arbitrary combination) and (B) an allyl carbonate compound (preferably allyl ester or crotyl ester) in the presence of (C) an organotin alkoxide using a platinum-group metal compound as a catalyst, at >=50 deg.C, preferably 70-150 deg.C. The amount of the component B is usually 0.8-5mol, preferably 1-3mol per 1mol of the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing α,β-unsaturated carbonyl compounds, and more specifically, the present invention relates to a novel method for producing α,β-unsaturated carbonyl compounds, and more specifically, it relates to a novel method for producing α,β-unsaturated carbonyl compounds by a novel external reaction using alkenyl esters and allyl carbonate esters as starting materials. The present invention relates to a method for producing a saturated carbonyl compound.

2-cyclobentenone, 2-cyclohexenone.

BACKGROUND OF THE INVENTION Alpha, beta-unsaturated carbonyl compounds such as 2-cyclodobcenone are useful chemical substances in the fields of fragrances, medicines, chemicals, and the like.

[7] The purpose of the present invention is to provide a method for efficiently synthesizing the α,β-unsaturated carbonyl compound by a novel reaction using easily available raw materials. An alkenyl ester represented by the formula [I] and an allyl carbonate ester are reacted at the lower right corner of an organotin alkoxide using a platinum group metal compound catalyst to form an α,β-unsaturated carbonyl represented by the following general formula [■]. The compound is 1t2 (in the above formula, R2, R3 and R4 are hydrogen or hydrocarbon residues, X is an acyl group, R1+ R2+
R3 and 4 may be chain-like, or each may form a chain in any combination. > In the present invention, as the first starting material, the general formula C
The alkenyl esters of I) are used. In the formula, 几1 is a hydrogen atom, a methyl group, -r-f, ](
, 7'robyl group, pentyl group, etc. 7 /l/
R2 is an alkylene group or an aryl group such as a phenyl group, a trityl group, etc. which is combined with Kyl3, R2, R11 or R4 to form a ring such as a cyclopenkune ring, a cyclohexane ring, a cyclododecane field, etc.
+ "3 and R4 mean a hydrogen atom or an alkyl group, alkylene group, or aryl group similar to 111, and roughly
means an acyl group.

Among the above substituents, R1, R2, R3 and R4 may each form a ring in any combination.

Specific examples of such compounds include 1-1-cyclohexenyl acetate, 1-cycloheptenyl acetate, 1-cyclododecenyl acetate, 1-cyclohexenylpropionate, 1-cyclohexenylbutyrate, 1-Cyclohexenylbenzoionate, 1-phenyl-1-butenyl acetate, 1-propenyl acetate, 1-hexenyl acetate, 6-methyl-1-butenyl acetate, 6-phenyl-1-propenyl acetate, etc. Illustrated. Among these, esters of cyclic olefins are preferred, and esters of 5- to 7-membered ring or 12-membered ring olefins are particularly preferred.

These compounds can be synthesized by conventional methods; for example, taking 1-cyclohexentylacetate as an example, a method in which cyclohexanone and isopropenyl acetate are reacted in the presence of an acid, a method in which cyclohexanone and acetic anhydride are reacted, etc. can be easily synthesized by

The allyl carbonate ester used as the second starting material is a carbonate ester having at least one allyl residue, and is usually a compound represented by the following general formula (III).

(In the formula, 1.1. represents a hydrocarbon residue, R6, R
7°■L8 and 几9 represent hydrogen or hydrocarbon residues. ) Examples of such compounds include methylallyl carbonate, ethylallyl carbonate, propylallyl carbonate, butylallyl carbonate, pentyallyl carbonate, methylcrotyl carbonate, ethylmethallyl carbonate, diallyl carbonate, and the like. Among these, allyl esters, crotyl esters, and methallyl esters in which R5 is a lower alkyl group having 4 or less carbon atoms are preferred.

In the present invention, a platinum compound catalyst is used in the reaction. Here, the platinum group metal compound catalyst refers to a platinum group metal compound itself or one consisting of a platinum group metal compound and a ligand.

The platinum group metal compound used is a salt or complex of palladium, platinum, rhodium, iridium, ruthenium,
Specific examples include tris(dibenzylideneacetone)dipalladium(0), )tris(tribenzylideneacetylacetone)tripalladium υ), palladium acetate, palladium propionate, palladium butyrate, palladium benzoate, palladium acetylacetonate, nitric acid. Palladium, palladium sulfate, palladium chloride, platinum acetate, platinum acetylacetonate, etc. are praised. When using a strong inorganic acid salt among these compounds, it is desirable to coexist a base such as potassium acetate, sodium alcoholade, or tertiary amine. Further, among the platinum group metals, palladium is particularly preferred in terms of reactivity, and among them, it is preferred to use a zero-valent olefin complex or a divalent organic compound.

The ligand used is an lli- or polydentate electron-supporting compound having an element of group Ⅰ of the periodic table, that is, nitrogen, phosphorus, arsenic, or antimony, as a coordination atom, and specific examples thereof include pyridine, quinoline, etc. , trimethylamine, triethylamine, triethylamine, α, α′-dipyridine, 1.10-7 enanthroline, N, 'N,
Nitrogen-containing compounds such as N',N'-tetramethylethylenediamine; triethylphosphine, tri-n-butylphosphine, tri-n-dodecylphosphine, triphenylphonphine, tri-o-tolylphosphine, tri-p-biphenylphosphine, tri- Methoxyphenylphosphine, phenyldiphenoxyphosphine, triethylphosphite, tri-n-butylphosphite,
Tri-n-hexyl phosphite, ■-riphenyl phosphite, tri-tolyl phosphite, triphenyl thiophosphite, α, β-ethylene di(diphenyl) phosphine, α, β-ethylene di(dibutyl) phosphine, α, γ ~ Arsenic-containing compounds such as propylene di(diphenyl)bosphine; Arsenic-containing compounds such as triethylarsenic, triptylyarsenic, triphenylarsenic, etc.; Antimony-containing compounds such as tripropylantimony, triphenylantimony, etc. can be mentioned. Among these, nitrogen-containing compounds and phosphorus-containing compounds are used in terms of reaction activity, selectivity, economy, and the like.

Although such a ligand is not necessarily essential as a catalyst component, by using an appropriate amount, the stability of the catalyst can be greatly improved.

The amount of the ligand used is not necessarily constant depending on the type, but in the case of monodentate ligands, it is usually 2.5 mol or less, preferably 0.1 to 2 mol, per 1 mol of the gold-14 compound.
Further, in the case of a difast ligand, the amount is usually 1.5 mol or less, preferably 1 to 1.2 mol.

The amount of catalyst to be used in the present invention is appropriately selected, but usually 0.01 platinum group metal compound per 100 moles of raw material.
-10 mol, preferably 0.1-5 mol. Also, the platinum group metal compound and the ligand may be reacted in advance, but +In 'ii supervision allows the catalyst to f! '! J
Manufactured.

In the present invention, the reaction is carried out in the presence of an organic tin alkoxide. The organic tin alkoxide used is a compound having one or more alkoxy groups bonded to a tin atom, and specific examples include tributyltin methoxide, tributyltin methoxide, tributyltin methoxide, tributyltin methoxide, tributyltin methoxide, and triphenyl. tin methoxide, tribenzyl tin methoxide, dibutyl phenyl tin dimethoside, dibutyl tin dimethoside, diptyl 7S diethoxide, dibutyl tin dibutoside, di, 4-poor tin dimethoside, diphenyl tin dimethoside. Among them, 17 tin monoalkoxides,
In particular, lower alkoxides are used as Tr in reactive songs.

The amount of 4A, 4tin alkoxide to be used can be selected as appropriate, but it is usually 1 mole of platinum alloy 1.S catalyst.
Force in 1-molar, t)-ft, /, 10I /r→')
, 1 n engineering 11. The reaction of the present invention is carried out by heating two starting materials in the presence of an organotin alkoxide and a catalyst. For example, the reaction formula for 'Jb combination using 1-cyclohexenyl acetate and methyl allyl carbonate is as follows.

The ratio of raw materials used is usually 0.8 to 5 moles of allyl carbonate, preferably 1 to 5 moles, per 1 liter of alkenyl ester.
The reaction humidity is usually 50°C or higher, preferably 70 to 150°C, and the reaction time is usually 10 minutes to 20 hours.

In addition, a diluent may be present during the reaction, specific examples of which include nitriles such as acetonitrile, propionitrile, butyronitrile, benzonitrile, etc.; Amides such as amide, dimethylpropioamide, N-methylpyrrolidone, etc.; Ethers such as tetrahydrofuran, dioxane, dibutyl ether, ethylene glycol dimethyl ether, etc.; acetone, methyl ethyl ketone, methyl isobutyl ketone Ketones such as , cyclohexanone, etc.; Esters such as methyl acetate, ethyl acetate, propyl acetate, ethyl propionate, etc.; Alcohols such as ethanol, propatool, ter-butanol, ethylene glycol, diethylene glycol monoethyl ether, etc.; dimethyl Examples include sulfoxides such as sulfoxide and diethyl sulfoxide; hydrocarbons such as n-hexane, cyclohexene, benzene, toluene, xylene, etc. Among them, aprotic polar solvents, especially nitriles, amides, ethers, Ketones and esters are awarded the prize.

These diluents are usually used in such a proportion that the concentration of the starting materials is 1 to 50% by weight, and their use can improve reaction activity, selectivity, and catalyst stability. In particular, when the catalyst component does not contain a monodentate ligand, the catalyst becomes unstable, so it is appropriate to use a diluent, and among them, it is preferable to use a nitrile.

After the reaction is completed, the target product is separated from the reaction solution according to a conventional method to obtain a highly pure α,β-unsaturated hydrocarbonyl compound, that is, an α,β-unsaturated ketone or an α,β-unsaturated aldehyde. . Such unsaturated carbonyl compounds are used as intermediates for the synthesis of various useful compounds, particularly for perfumes, medicines, and the like.

Thus, according to the present invention, α, β-
Unsaturated hydrocarbonyl compounds can be produced.

The present invention will be explained in more detail with reference to Examples below.

Example 1 2 moles of methylallyl carbonate, 95 moles of acetonitrile, 0.05 moles of palladium acetate, and 0.2 moles of tributyltin methoxide were charged to 1 mole of 1-cyclohexenyl acetate in a volume rl, and the mixture was rapidly stirred at room temperature. Thereafter, the temperature was raised to the boiling point of the solvent, and the reaction was carried out under reflux in an argon atmosphere for 10 hours. After the reaction was completed, the product was distilled under reduced pressure according to a conventional method, and as a result, 2-cyclohexen-1-one (hereinafter referred to as CHE) was obtained with a yield of 95%. Note that these compounds can be identified using IR and NMR.
and mass spectroscopy.

Example 2 A reaction was carried out in the same manner as in Example 1 except that 0.05 mol of triphenylphosphine was added in addition to palladium acetate, and the yield of CHB was 97%.

Example 6 α, β-ethylene di(
The reaction was carried out in the same manner as in Example 2 except that 0.05 mol of diphenyl)phosphine was used)-;'-7,
-CHI+】(MJV'Mt-IQ7%'F book-f-
- Example 4 The reaction was carried out in the same manner as in Example 6 except that 0.05 mol of tris(dibenzylidene-heptadone)dipalladium (0) was used in place of palladium acetate.
The yield of HE was 86%.

Example 5 The reaction was carried out in the same manner as in Example 6 except that the amount of tributyltin methoxide used was reduced to 0.1 mole, and the yield of CHE was 54%.

Example 6 The reaction was carried out in the same manner as in Example 2 except that tributyltin propoxide was used in place of tributyltin methoxide, and the yield of CI(E) was 60%.

Example 7 A reaction was carried out in the same manner as in Example 6 except that the compounds shown in Table 1 were used as starting materials.

The results are shown in Table 1.

Table 1 Example 8 The reaction was carried out in accordance with Example 6 except for using 1-cyclopentenyl acetate as the base phase and changing the solvent from acetonitrile to benzene. was obtained with a yield of 59%.

Patent applicant: Zeon Corporation

Claims (1)

[Claims] 1 General formula CI) (wherein, R+ + "2 + 几3 and J (.4 represents hydrogen or a hydrocarbon residue, X represents an acyl group, R1°R,... R, 3 and 几4 may be chain-like or each may form a ring in any combination) and the allyl-type carbon N&ester are combined with a platinum group metal in the presence of an organic tin alkoxide. The general formula [■]■ is also represented by 2 (in the formula, ■ is also 1 r ``2 + ''3 and R4 are the same as above). A method for producing an α,β-unsaturated carbonyl compound.