JPS59186938A - Preparation of alpha,beta-unsaturated carbonyl compound - Google Patents

Abstract

PURPOSE:To prepare the titled compound useful in the fields of perfumery, pharmaceuticals, chemicals, etc., in high yield, by using an alkenyl silyl ether and an allyl carbonate as raw materials, and reacting the materials in the presence of a catalyst. CONSTITUTION:The objective compound of formula II can be prepared by reacting (A) 1mol of an alkenyl silyl ether of formula I (R1, R2, R3 and R4 are H or hydrocarbon residue; X is trihydrocarbylsilyl group; R1, R2, R3 and R4 may be linear or may form rings at an arbitrary combination) (e.g. 1-cyclohexenyl trimethylsilyl ether) with (B) 0.8-5mol, preferably 1-2mol of an allyl carbonate (e.g. diallyl carbonate), in the presence of a catalyst comprising alpha,omega-alkylene di(disubstituted)phosphine, preferably in the presence of a diluent such as acetonitrile.

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, α,β- Regarding the method for producing unsaturated carbonyl compounds Unsaturated carbonyl compounds such as cyclohentenone a conductors, cyclohexenone derivatives, cyclodobcenone derivatives, etc. are useful chemical substances in the fields of fragrances, medicines, chemicals, etc.

As a method for synthesizing such unsaturated carbonyl compounds, a method by isomerization of a compound having an extracyclic double bond such as alkylidenecyclopentanone has been known (for example, Japanese Patent Application Laid-Open No. 51-23240 In this case, the reactivity was not uniform depending on the type of side chain, and it was actually suitable for the synthesis of compounds with unsaturated bonds in the side chain, such as alkenylcyclobentenone.

Therefore, the present inventors conducted intensive studies to develop a method that would enable the synthesis of the desired unsaturated carbonyl compound regardless of the type of side chain. We have discovered a new reaction using starting materials and have completed the present invention.

Thus, according to the present invention, the formula represented by the following general formula CI) □
The alkenyl silyl ether and allyl carbonate ester are brought into contact with each other in the presence of a catalyst consisting essentially of a platinum group metal compound and α-alkylene di(disubstituted) phosphine (abbreviated as ADP). A method for producing an α,β-unsaturated carbonyl compound represented by the following general formula [■] is provided.

(In the above formula, RI * RI + R8 and R1 represent hydrogen or a hydrocarbon residue, or a trino-hydrocarbyl silyl group, and R1 * RR * RI * R4 may be a chain or each of They may be combined to form a ring.

In the present invention, the first starting material is the general formula [
An alkenylsilyl ether represented by [E] is used. In the formula, R3 is not only a hydrogen atom but also a methyl group, an ethyl group,
Alkyl groups such as propyl group, pentyl group, R,
, R, or R4 to form a ring such as a cyclobentane ring, a cyclohexane ring, or a cyclododecane ring. RI * R1 and R
4 means a hydrogen atom or an alkyl group, an alkylene group, or an atomyl group similar to R1, and X means a torinohydrocarbylsilyl group. Among the above substituents, R,
, R, , R, and R4 may each form a ring in any combination. Specific examples of such compounds include 1-cyclohexenyl trimethylgril ether, 1-cyclopentenyl trimethylsilyl ether, 2 -Methyl-1-cyclohexenyltrimethylsilyl ether, 6-methyl-
1-Cyclohexenyltrimethylsilyl ether, 1-
Cyclododecenyltrimethylsilyl ether, 1-cyclohexenyltriethylgril ether, 1-7 clohexenyltripropylsilyl ether, 2-pentenyl-1-cyclohexenyltrimethylsilyl ether, 2
-7'a pyl-1-cyclohexenyl trimethylsilyl ether, 2-pentyl-1-cyclohexenyl trimethylsilyl ether, 2-pentyl-1-cyclopentenyl trimethylsilyl ether, 2-pentenyl-1
-Cyclopentenyl trimethylgril ether, 2-pentynyl-1-cyclopentenyl trimethylsilyl ether, 1-phenyl-1-butenyl trisilyl ether, 1-7' lobenyl trimethylsilyl ether, 1-hexenyl trimethylsilyl ether, 2-methyl -1-
Butenyltrimethylsilyl ether, 3-methyl-1-
Butenyl trimethylsilyl ether, 3-phenyl-1
-propenyltrimethylsilyl ether and the like.

These compounds can be synthesized according to conventional methods. For example, 1-cyclohexenyltrimethylsilyl/l/ni
For example, allyl-type carbonate ester used as the second starting material can be easily synthesized by a method of reacting cyclohexanone with trimethylsilyl chloride in the presence of a base. It is a carbonate ester having a type residue, and is usually a compound represented by the following general formula CI).

(In the formula, R1 represents a hydrocarbon residue, R,,R,.

R and R6 represent all hydrogen or hydrocarbon residues. ) Specific examples of such compounds include diallyl carbonate, dicrotyl carbonate, dimethallyl carbonate, methylallyl carbonate,
Examples include ethyl allyl carbonate, propyl allyl carbonate, butyl allyl carbonate, pentyl allyl carbonate, methyl crotyl carbonate, and ethyl metaallyl carbonate. Among these, allyl esters, crotyl esters, and methallyl esters in which R1 is a lower alkyl group or lower alkenyl group having 4 or less carbon atoms are preferred.

In the present invention, a platinum group metal compound and A
The platinum group metal compounds used in the catalyst consisting essentially of DP are salts or complexes of palladium, platinum, rhodium, iridium, ruthenium, and any metal that can form a complex with ADP can be used. Specific examples of such compounds include tris(tribenzylideneacetylacetone)nipalladium(0), )tribenzylideneacetylacetone)tripalladium(0),
Examples include palladium acetate, palladium acetylacetonate, palladium nitrate, palladium sulfate, and radium chloride. 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. Furthermore, among the platinum group metals, palladium is particularly preferable in terms of reactivity, and among them, it is preferable to use zero-valent compounds or divalent organic compounds.On the other hand, as specific examples of ADP, for example, α, β-ethylenedi(diphenyl)phosphine, α,β-ethylenedi(diethyl)phosphine, α,β-ethylenedi(dibutyl)phosphine, α,β-ethylenedi(phthylphenyl)phosphine, α,γ-propylene di(diphenyl)
Examples include phosphine, α, δ-butylene di(diphenyl) phosphine, and among them, α, β-ethylene diphosphine, especially α, β-ethylene di(diphenyl) phosphine. Incidentally, α,β-ethylenedi(diphenyl)phosphine is represented by the following structural formula.

(In the formula, ph represents a phenyl group.) The ratio of these two components used is selected as appropriate, but is usually per mole of platinum group metal compound.) ADP 0.5 mole or more, preferably 0
．． Catalysts consisting of both components with 7 to 1.5 moles of platinum group metal compound per 100 moles of raw material are usually 0.01 to 1.5 moles of platinum group metal compound per 100 moles of raw materials.
It is used in such a proportion that it is 10 moles. Although these two components may be reacted in advance, the catalyst is usually prepared by bringing both components into contact in a reaction system.

The reaction of the present invention proceeds easily by bringing two starting materials into contact with a catalyst. For example, 1-
The reaction formula when using cyclohexyltrimethylsilyl ether and diallyl carbonate is shown below.

The proportion of raw materials used is 1 mol of alkenyl silyl ether, usually 0.8 to 5 mol, preferably 1 to 2 mol of allyl carbonate, reaction temperature is usually sac or higher, preferably 60 to 150 C, and reaction time. is usually 10 minutes to 10 hours.

In addition, it is preferable to have a diluent present during the reaction from the viewpoint of improving selectivity, and specific examples thereof include acetonitrile, propionitrile, benzonitrile, dimethylformamide, dioxane, etc. These diluents are commonly used. They are used in proportions such that the concentration of the voice starting material is 1 to 50% by weight.

After completion of the reaction, a highly purified α,β-unsaturated carbonyl compound, that is, an α,β-unsaturated ketone or an α,β-unsaturated aldehyde, is obtained by separating the target product from the reaction solution according to a conventional method. Such unsaturated carbonyl compounds are used as intermediates for the synthesis of various useful compounds, particularly for perfumes, medicines, etc. Thus, according to the present invention, by utilizing a novel reaction, α can be efficiently , β-unsaturated carbonyl compounds can be produced.

The present invention will be explained in more detail below by giving Examples.

Example 1 In a container, 8 mol of 1-cyclohexenyltrimethylsilyl ether nitrile, 0.05 mol of palladium acetate and α,
β-ethylenedi(diphenyl)phosphine was charged at a ratio of 0.05 mol, and after stirring rapidly at room temperature, the temperature was raised to the boiling point of the solvent, and the reaction was carried out under reflux under an argon atmosphere for 1 hour. 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 was obtained in a yield of 87%. In addition, the identification of these compounds was carried out by Engineering R,N
O conducted by using MR and mass spectra Examples 2 to 6 Reactions were carried out in the same manner as in Example 1 except that the compounds shown in Table 1 were used as starting materials. Results first
Shown in the table.

Table 1 Example 7 The reaction was carried out in the same manner as in Example 1 except that the amount of catalyst used was reduced to 115 and the reaction time was extended to 5 hours. As a result, 2-cyclohexen-1-one was obtained. Leadership 6
It was 0%.

Example 8 A reaction was carried out according to Example IK except that palladium acetylacetonate was used in place of palladium acetate, and almost the same results as Example 1 were obtained.

Example 9 A reaction was carried out according to Example 2 except that tris(dibenzylideneacetone)nipalladium (0) was used in place of palladium acetate, and almost the same results as in Example 2 were obtained.

Example 10 The reaction was carried out according to Example 1 except for using 1-cyclopentenyltrimethylsilyl ether as a raw material and changing the solvent from acetonitrile to benzonitrile. 2-cyclopenten-1-one was produced in a yield of 70%. obtained at a rate.

Patent Applicant Nippon Zeon Co., Ltd. Procedural Amendment 1. Description of the case Japanese Patent Application No. 58-60581 2 Title of the invention α, Process for producing β-unsaturated carbonyl compound 5 Person making the amendment 5 Column for detailed description of the invention in the specification to be amended & Contents of the amendment 11+ "Aceto" on page 11, line 9 of the specification is corrected to "2 moles of diallyl carbonate, aceto."

that's all

Claims (1)

[Claims] 1 General formula IJ) (wherein RI + J + u and R4 are hydrogen or hydrocarbon residues, X represents a trihydrocarbylsilyl group, and RI, Ra + Ra and R4 are A platinum group metal compound and an α,ω-alkylene di(disubstituted) phosphine are prepared by combining an alkenylsilyl ether (which may be chain-like or each may form a ring in any combination) and an allyl carbonate ester with a platinum group metal compound. Contacting in the presence of a catalyst consisting essentially of '? General formula [1] characterized by (
Method 0 for producing an α,β-unsaturated carbonyl compound represented by the formula (R1R11 R8 and R4 are the same as above)