JPS5951530B2 - Method for producing τ-unsaturated carboxylic acid ester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on the general formula R(O Carbon number 5
A higher alkyl group, a benzyl group, or a phenoxybenzyl group containing 1 or more.

) The present invention relates to a method for producing a γ-unsaturated carboxylic acid ester represented by: More specifically, the present invention is based on the general formula R2R3C=CH-C-0H (■)
Allyl alcohol derivatives represented by the general formula R1CH2C(0H7)3 (in the formula, R'' is hydrogen, a lower alkyl group, or a cycloalkyl group); It is a cycloalkyl group, and R7 is a lower alkyl group.

) and the general formula R
60H... (■) (In the formula, w is a higher alkyl group containing 5 or more carbon atoms, a benzyl group, or a phenoxybenzyl group.) By reacting the alcohol represented by () in the presence of an acidic catalyst, the above The present invention relates to a method for producing a monounsaturated carboxylic acid ester represented by general formula (I).

The r-unsaturated carboxylic acid ester represented by the general formula (1) is useful as an intermediate for the synthesis of units constituting the acid moiety of synthetic pyrethroid compounds, which are attracting attention for their usefulness as insecticides.

Conventionally, insecticides such as DDT and B. H. However, due to its residual toxicity, there is a strong demand for non-polluting insecticides.

From this point of view, pyrethroids, which have been extracted from natural products and used since ancient times, are newly attracting attention due to their low pollution and insecticidal ability. A disadvantage in the use of natural pyrethroid insecticides is that they biodegrade quickly. As a result of a thorough search for a compound that solves this drawback and has insecticidal efficacy superior to that of natural pyrethroids, a derivative of chrysanthemum acid with a modified dimethylvinyl group has been shown to have a long-lasting and excellent insecticidal effect. A synthetic pyrethroid was discovered. [M. E
IIlOtt, etaLNature, 244, 456
(1973)] The present invention provides a method for producing an r-unsaturated carboxylic acid ester represented by the general formula (1), which is useful as a precursor of the cyclopropane carboxylic acid ester for synthetic pyrethroid. be.

Conventionally, in order to convert the dimethylpinyl group of chrysanthemum acid, a method has been proposed in which chrysanthemum acid itself is used as a starting material and a new substituent is introduced after ozonolysis. However, this conventional method has drawbacks such as the use of expensive chrysanthemum acid and the long and complicated synthesis route. [Unexamined Japanese Patent Publication No. 49-47531 or D.
G. BrOwn, etaLyu, J. Agr. FOOd.
, 2l, 767 (1973)] Furthermore, conventionally, as a method for producing r-unsaturated carboxylic acid ester, 3-methylcrotyl alcohol and vinyl ether are condensed, and the formed r-unsaturated aldehyde is oxidized and esterified. A method has been proposed. [J. Am. Chem. SOc.
, 82, 468l-5 (1960)]. However, this conventional method not only requires relatively expensive reagents such as vinyl ether, but also requires a long reaction process, making it difficult to adopt as an industrial method.

There is also a method proposed by the present inventors in order to solve such conventional drawbacks.

This method proposed by the present inventors is characterized by the use of a lower alkyl ester of orthoacetic acid; requires further transesterification after completion of the reaction. Therefore, for the above purpose, it is desirable to be able to produce higher alkyl or aralkyl esters simultaneously with the completion of the reaction. On the other hand, when a lower alkyl ester of orthoacetic acid is used as a raw material, the boiling points of this raw material and the lower alkyl ester of an r-unsaturated carboxylic acid, which is the reaction product, may be relatively similar; There are cases where separation is somewhat difficult. Therefore,
The development of a method for directly producing higher alkyl esters or aralkyl esters can be said to be highly useful from a technical standpoint. The present inventors aimed to establish a method that met these objectives, and as a result of extensive studies, we found that in the condensation of lower alkyl esters of orthocarboxylic acids and allyl alcohols, higher alkyl alcohols or aralkyl alcohols were added to the reaction system. The present inventors have discovered that the desired r-unsaturated carboxylic acid ester represented by the above-mentioned general formula (1) can be selectively obtained when the above-mentioned formula (1) is co-present, leading to the completion of the present invention.

The allyl alcohol derivative represented by the general formula (2) used as a raw material compound in the method of the present invention includes 3-
Methyl-2-buten-1-ol, 4-methyl-3-benzen-2-ol, 2,4-dimethyl-3-benzen-2-ol, 5-methyl-4-hexen-3-ol, 2- Examples include methyl-5-hepten-4-ol and 1-cyclopentyl-3-methyl-2-buten-1-ol.

All of these allyl alcohol derivatives are compounds that can be easily derived from industrial raw materials. Examples of the alcohol represented by the general formula () include higher alkyl alcohols containing 5 or more carbon atoms such as octyl alcohol, decyl alcohol, and dodecyl alcohol, benzyl alcohol, O-phenoxybenzyl alcohol, and M-phenoxybenzyl alcohol. Examples include alcohol and phenoxybenzyl alcohol such as P-phenoxybenzyl alcohol.

The present invention requires the presence of an acidic catalyst.

Acidic catalysts include phenol, O-M-, or P-nitrophenol, O-, M-, or p-cresol, o-
-, m-, or p-xylenol, 2,6-dimethylphenol, 2,6-di-t-butylphenol, 2,
4,6-tri-Sec-butylphenol, 2,4,
6-tri-t-butylphenol, 4-methyl-2,
6-di-t-butylphenol, 4-methyl-3,5
-di-t-butylphenol, hydroquinone, 2,5
-di-t-butylhydroxins, phenols such as α,β-naphthol, lower fatty acids such as acetic acid, propionic acid, butyric acid, isobutyric acid, cyclohexanecarboxylic acid, valeric acid, benzoic acid, m-chlorobenzoic acid Aromatic carboxylic acids such as acids, sulfonic acids such as benzenesulfonic acid and para-toluenesulfonic acid, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and boric acid, aluminum chloride, zinc chloride,
Examples include iron chloride, boron trifluoride, vinegar, and Lewis acids such as mercuric monoate, but in order to avoid side reactions such as dehydration of the raw materials of formula (self), phenols and carbon atoms are preferably used. 2 to 6 fatty acids, aromatic carboxylic acids, boric acid, phosphoric acid, etc. are used. The amount of catalyst used is in the range of 0.001 to 20% by weight, preferably in the range of 0.01 to 15% by weight, based on the raw material allyl alcohol 2-ol derivative. A reaction solvent is not necessarily required, but if desired, n-octane, toluene, o-, m-, or P2-xylene, di-n-butyl ether, t-butyl alcohol, N,N-dimethylformamide, etc. can be used directly in the reaction. Non-participating media can be advantageously used.

Although the reaction temperature is not limited, it is preferably in the range of about 100 to 200°C from the viewpoint of reaction rate and selectivity. The present invention will be explained in more detail with reference to 3 Examples below.

Example 1 Ethyl orthoacetate 8.1y and prenol 4.
39 and n-octyl alcohol 6.59;
Added 1 drop of isobutyric acid and heated and stirred at 130°C for 2 hours 3
Thereafter, heating and stirring were continued at 150° C. for 15 hours.

By distillation after cooling, the boiling point is 103-105℃A. 2. So-called Hg
5.49 of n-octyl 3,3-dimethyl-4-benzenate was obtained. Nuclear magnetic resonance absorption (CCI) of 45% yield product.

δ)! 5.85 (D.d4H), 5.10-4.70
(M.2H), 3.95 (B.t.2H), 2.18 (
S. 2H). 126 (M.l2H), 1.06 (S.6
H), 084 (B.t.3H) Example 2 Mix 0.81 g of ethyl orthoacetate with 0.43 I of prenol and 0.55 g of benzyl alcohol, and add succinic acid to 2W1f1.
The mixture was heated and stirred at 130°C for 2 hours, and then heated and stirred at 150°C for 15 hours.

When this crude product was quantified by gas chromatography, it was found that the desired benzyl 3,3-dimethyl-4-benzenate was produced in a yield of 25%. Nuclear magnetic resonance absorption (CCl4δ) of the product 7.29 (B.s.

5H), 5.84 (D.d.IH), 5.10-4.7
0 (M.4H), 2.22 (S.

2H), 1.06 (S.6H) Example 3 0.81 g of ethyl orthoacetate, 0.43 I of prenol and 1.09 m-phenoxybenzyl alcohol were mixed, 1 drop of isobutyric acid was added, and 130 g of ethyl orthoacetate was mixed. After stirring at 150°C for 2 hours, heating and stirring was continued at 150°C for 16 hours.

From this crude product, boiling point 155-158℃/
0.46 g of m-phenoxybenzyl ester of 3,3-dimethyl-4-benzenic acid was obtained as an oil having a pressure of 0.3 nHg. Nuclear magnetic resonance absorption of 30% yield product (
CCl4δ) 7.32-6.70 (M.9H), 5.76 (D.d.
IH) 4.92 (S.

2H), 4.95-4.70 (M.2H), 2.22 (
SO2H), 1.08 (SO6H) Example 4 1.62 g of ethyl orthoacetate and 4-methyl-3-benzene-
Mix 1.0g of 2-ol and 2.0θ of m-phenoxybenzyl alcohol, add 30Tf9 of isobutyric acid,
After stirring at 130°C for 2 hours, stirring was continued at 150°C for 15 hours.

From this crude product, boiling point 152-155℃/
0.849 m-phenoxybenzyl ester of 3,3-dimethyl-4-hexenoic acid was obtained as an oil with 0.1-Hg. Yield 26% Nuclear magnetic resonance absorption of product (CCl4, δ) 7.4-6.
7 (M, 9H), 5.7-5.3 (M, 2H), 4.9
2 (S, 2H), 2.15 (S, 2H), 1.65 (B
．． d, 3H), 1.10 (S, 6H).

Claims (1)

[Claims] 1 Allyl alcohol derivative represented by the general formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ General formula R^1C
There are general formulas▲mathematical formulas, chemical formulas, tables, etc.▼ that are characterized by the reaction of orthocarboxylic acid esters represented by H_2C(OR^7)_3 and alcohols represented by the general formula R^6OH in the presence of an acidic catalyst. A method for producing an r-unsaturated carboxylic acid ester represented by [wherein R^1, R^2, R^3, R^4 and R^5]
is hydrogen, a lower alkyl group or a cycloalkyl group,
R^6 is a higher alkyl group containing 5 or more carbon atoms, a benzyl group or a phenoxybenzyl group, and R^7 is a lower alkyl group.