JPS5965035A - Preparation of trans-isoeugenol and its derivative - Google Patents

Abstract

PURPOSE:To prepare the titled compound having excellent fragrance economically, in an improved selectivity, by contacting eugenol or its derivative with an isomerization catalyst comprising iridium tetrachloride or its monohydrate. CONSTITUTION:The objective compound of formula II can be prepared easily, in a remarkably excellent selectivity (about 97-99%) and high yield (about >=99%), by contacting the eugenol of formula I (R is H, 1-6C alkyl, <=8C aralkyl, or 1-6C acyl) or its derivative with the easily available and preparable catalyst of formula IrCl4.nH2O (n is 0 or 1) in the presence or absence of water. The amount of the catalyst is preferably about 0.001-0.1wt%, especially about 0.01-0.1wt%, based on the compound of formula I . Preferably, the reaction is carried out in the presence of water to attain rapid reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the method for producing diine eugenol and its conductor by bringing eugenol and its hinderer into contact with an isomerization catalyst to cause an isomerization reaction. , I is a chloride of Kaede 1r, which belongs to period 6 of group Ⅰ of the periodic table and has never been proposed as an isomerization catalyst.
rC; L, ·nli, 0 (herein, R is 0 or 1) 1 By bringing it into contact with oilnol and its derivatives in the presence of water or in the presence of water to cause an isomerization reaction, The present invention relates to a method for producing trans-isoeugenol and its derivatives, which can produce trans-isoeugenol with significantly improved selectivity and excellent aroma in high yield.

Further aspects of the present invention are as follows.

The following formula (2) However, in the formula, Nosy is HlC, to C6 alkyl group.

It represents a group selected from the group p, such as an aralkyl group up to C8 and a C, to C3 acyl group.

Eugenol and its derivatives represented by.

1rcl, -nli, 0 (where n is 0 or t
(1) The following formula +1) characterized by bringing the isomerization reaction into contact with a catalyst in the presence or absence of water.
However, in the formula, R has the same meaning as described above, and relates to a method for producing trans-isoeugenol and its derivatives represented by:

It has been known that eugenol and its derivatives represented by the above formula (2) are brought into contact with an isomerization catalyst to cause an isomerization reaction to produce eugenol and its derivatives.

For example, as introduced as prior art in Japanese Patent Publication No. 52-45697, Ru1. Rice, Gase Arca IJ f
A method is known in which a fluorocarbon catalyst is used as a catalyst, but this method requires the use of linear temperature conditions, and in particular, for the isomerization reaction of eugenol, caustic alkali metal of at least an equimolar amount with eugenol is required. However, in addition to the fact that the alkaline salt of eugenol and the produced isoeugenol becomes a single reaction product, there are disadvantages to the reaction operation in terms of stirring operation, reaction temperature control, etc., and the one-stroke conversion rate is about 85%. ~about 90%, trans form production rate about 60 to about 70
Even if it is about 1%, it gives an unfavorable shadow to the desired aroma of trans-integrated products, and it is unsatisfactory because industrial refining methods cannot avoid separation and generation of cis-integrated products. Met.

With the full intention of improving such conventional methods, the formula (2) eugenol and its derivatives are added to period 5 of group Ⅰ of the periodic table.
A complex catalyst of metal Pd that is scraped, and the complex single-layer plate portion 9
The above-mentioned Japanese Patent Publication No. 52-45697 proposes that the isomerization reaction is caused by contact under conditions that require the presence of 5 to 2000 parts by weight of alcohol.

In this proposal, it is disclosed that it is essential to carry out the isomerization reaction in the presence of an alcohol in the above-mentioned specific range. Furthermore, in this proposal, the yield of the tetramerization product is sufficiently high depending on the type of Pd complex, and in the case of an expensive organic tsucladium complex that is difficult to obtain on the market and must be produced by complicated means. Inorganic palladium complexes such as PdC1, which are readily available on the market and easy to manufacture, have yields of isomerized products exceeding 99%.

In the case of PdBr, , K, and PdC14, it has been shown that the yield of isomerized products is about 93-96%. Furthermore, in this proposal, the trans integral selectivity is approximately 93% for both organic and inorganic palladium complexes.
Even if it is a polar layer, industrial Japanese manufacturing methods still fail to avoid separation and generation of cis-integral substances in amounts that have an unfavorable effect on the buds.

The present inventors have developed a method capable of producing aromatically aromatic trans-1 sooirnol of formula (1) and its derivatives with further improved and satisfactory isomerization product yield and trans integral selectivity. We have been conducting research to develop it.

As a result, IrC1,·nli,O (where n is 0 or l
) is the above formula (2) eugenol and its derivative t-
, formula (1) is intended to be used as an isomerization catalyst for isomerizing trans-inoyl-nor and its hydrogen donor, with an isomerization product yield of about 99% or more, and Producing the compound of formula (1) with a trans integral selectivity of about 97% or even higher, reaching about 99%.
(I-I discovered it.

Historically, there is no need to use alcohols, which are essential in the above conventional proposals, and the IrCL of the present invention.

・In the isomerization reaction by nli, 0, it was unexpectedly discovered that water increases the reaction coupling, which is a unique reaction mechanism. This unique reactor'rW
The details of Ruka 1) 6 bright I rCl, ・nl
The increase in the reaction rate caused by water in the tetrasexualization reaction of the 0 tentacles to the upper Mr2 was also completely unexpected.

Therefore, one object of the present invention is to bring eugenol and its derivatives into contact with an isomerization catalyst to easily produce trans-isoeugenol and its derivatives with significantly improved selectivity, high yield, and fragrance value. We are here to provide you with a method.

The above objects and many other objects and advantages of the present invention will become more apparent from the following description.

In the present invention, eugenol and its derivatives included in the above formula (2) include 10,000 ignol, O-methyl eugenol, 0-enal eugenol, O-propyl eugenol, O- Gtyloeugenol, O-amyl eugenol.

O-inamyl eugenol, O-hexyl eugenol, 10-pendulu eugenol, formyl eugenol, acetyl eugenol, propionyl eugenol, 0-methylacetyl eugenol, O-methylformyl eugenol, O-methylgropionyl oil
Examples include nol.

In addition, Ir used in the present invention (,:14 and/or lr
(:l, ・The certificate of use for the H3O catalyst can be selected as appropriate, but
1 for the previous HL' compound of formula (1), for example, about 0.001
~about O1, more preferably, for example, about o,oi
The entire range of about 0.1 to about 1 inch can be shown.

The reaction is between the compound of formula (2) and IrC1,·nH,0 (here.

n is 0 or l)) The reaction can be carried out by contacting the catalyst with -F'KW in the presence or absence of water.

The above-mentioned isomerization reaction t is preferably carried out in the presence of water because the reaction proceeds quickly. There are no special restrictions on the use of water.
:Ii! i+can be selected as desired.

For example, IrCl4 and/or IrCl, -Hlo
About 1 to about 100,000 jushabu per 1 heavy kiibu,
More preferably? Examples include toilet lids ranging from f-Jlθ to about 10.000 parts by weight.

In carrying out the method of the present invention, the reaction time and reaction temperature are as follows: 1. Catalyst O (can be selected as appropriate depending on the Ryu 1 and 191 fan, etc., but v'sueha.

Generally, the reaction time is about 10 minutes to about 20 hours, the reaction temperature is about 20-1 to about 150C, and preferably the reaction time is about 0.5 to about 1 OtjJ, and the reaction temperature is about 20-1 to about 150C. It is possible to show a range of about 40 to 100C. The reaction operation is extremely easy.

For example, the desired product can be obtained by mixing eugenol and its derivatives represented by the above formula (2) with the above catalyst and water in a suitable reaction vessel, and heating or simply stirring without heating. Trans-isoeugenol and its derivatives represented by formula (1) are obtained.

Although the reaction can generally be carried out without diluent or vehicle,
If desired, an inert diluent or medium that does not inhibit the isomerization reaction, such as ethyl nitride, tetrahydrofuran, dimethoxyethane, penzene, toluene, xylene, pentane, hexane, octane, tethane, sochloromethane, ethyl acetate, Dimethylformamide, trimethylsulfoxide, methanol, ethanol, propatool.

It can be carried out by adding all butanol, hexanol, etc.

Hereinafter, several examples of implementing the method of the present invention will be described by way of examples.

Example 1 Production of isooike9nol Eugenol2
231 pieces of 301% 1 rcl, 0.1 t oyohi water were placed in a reaction vessel and reacted at 95C for 2 hours. When the reaction is complete, water is removed and distilled under reduced pressure to produce a distillate of 228?
(Yield 99.1) was obtained. The isomerization products (including isoforms) of this product were tj, tooochi, and the trans isomer was 98.2chi. Analysis fiGC-MS
Approved by V&.

Example 2 Preparation of Isoeugenol Oil No A, 100f and IrCl4-11.00.
05f'i! Place in an Il-reaction vessel and react at 100r for 6 hours. After the reaction is completed, tMc pressure distillation is performed to obtain a distillate of 98.
．． 5F (yield 9 & 5%) was obtained. This product must contain 99.8% isomeric products (including isoforms).

In addition, the trans isomer content was 98.8%. The news was confirmed by GLC.

Examples 3 to 8 Various raw materials included in the formula +11 shown in Table 1 below were tested in the same manner as in Example 1 using the conditions shown in Table 1 below. The results are shown in 1st M.

Claims (1)

[Claims] 1. The following formula (2), where R is selected from the group consisting of #, (, ', ~C6 alkyl group, aralkyl group up to Ca゛, and ~Ca acyl group, etc.) Eugenol and its derivatives represented by: IrUl, -nli, U (where n is 0 or 1) are brought into contact with a catalyst in the presence or absence of water to cause an isomerization reaction. A method for producing trans-in eugenol and its derivatives represented by the following formula (1), wherein Rii is the same as 1 above.