JPS6236342A - Production of malonic acid diester - Google Patents

Abstract

PURPOSE:To readily improve the yield with a high catalyst efficiency and simple operation, by reacting a halogenated acetic acid ester with carbon monoxide and alcohol in the presence of a rhodium compound as a catalyst to obtain the titled compound useful as a raw material for medicines, etc. CONSTITUTION:A halogenated acetic acid ester as a raw material is catalytically reacted with carbon monoxide and an alcohol in the vapor phase in the presence of a rhodium compound and a coexisting iodine compound, preferably at 100-300 deg.C to afford the aimed compound. Examples of the rhodium compound to be used as the catalyst include PhCl3.3H2O, PhBr3-2H2O, Rh(NO3)3, etc., and the rhodium compound is particularly preferably used by supporting on active carbon. The amount of the compound to be supported is 0.5-20wt% based on the carrier. NaI, KI, etc., may be preferred for the iodine compound, and supported on the carrier in use thereof. The amount of the iodine compound to be added is preferably at 1:0.1-1:10 molar ratio based on the rhodium compound.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a method for producing malonic acid diester.

Malonic acid diester is used as a raw material for medicines, agricultural chemicals, dyes, etc., and it is desired to establish an inexpensive method for producing it.

The present invention relates to an improved method for producing malonic acid diester by reacting a halogenated acetate with carbon monoxide and alcohol.

(Prior Art) Conventionally, a method has been proposed for producing malonic acid diester ta by reacting a halogenated acetic ester with carbon monoxide and alcohol, and Japanese Patent Publication No. 16134/1983 discloses the following method:
An improved method was proposed in which a gas phase catalytic reaction is carried out in the liquid phase with an alcohol in the presence of a base, a rhodium catalyst, and optionally an iodine compound.

(Problems to be Solved by the Invention) The conventional methods of producing malonic acid diester by reacting these halogenated acetic esters with carbon monoxide and alcohol have the following problems.

(1) All of these methods produce a small amount of malonic acid diester per unit amount of catalyst.

(2) The method of reacting liquid halogenated acetate ester involves uniform mixing with a large number of basic compounds in order to capture the halogen produced in the reaction, and the halogenated metal salt after the reaction is complex operations such as filtration and extraction are required to separate malonic acid diester from malonic acid diester and catalyst.The present invention solves these problems and provides efficient malonic acid diester with simpler operations. This is the result of extensive research in order to provide a manufacturing method.

(Means for Solving the Problems) The present invention provides a gas phase catalytic reaction in the presence of an iodine compound in reacting a halogenated acetate with carbon monoxide and alcohol in the presence of a rhodium compound.
This is a method for producing malonic acid diester.

The present invention will be explained in more detail below.

The halogenated acetate used in the present invention is not particularly limited as long as it has a boiling point of 250°C or less, but lower argyl esters such as methyl, ethyl, n-progyl, isozolobyl, butyl are preferable, and halogen substituents The alcohol used in the present invention is not particularly limited as long as it is an aliphatic alcohol having 1 to 8 carbon atoms. Alcohol is preferred. For example, methanol is used in the case of halogenated methyl acetate, and isopropyl alcohol is used in the case of halogenated isozolovir acetate.

The carbon monoxide used does not need to be particularly pure;
It is also possible to use one in which an inert gas coexists.

In the present invention, the rhodium compound used as a catalyst,
Rhodium halide, inorganic acid salt or complex compound, examples include RhCj3@5H20, RhBr5
I2H20, Rh(NO3)3, RJ(Co
)4Cj2, Rh(Co)CJ()(C6
Hs)s]z.

Rhcj(P(06Hs)313, Rb403s5
H20, (NH4)3RhCj6.

h engineering 3'3CH20 etc. These compounds do not need to be highly pure, and may contain salts such as sodium chloride and potassium chloride.

In the present invention, the iodine compound added to the catalyst is
Metal iodides are used. For example, Li engineering.

K work, Na work, Ba work, , Cs work, Rb work,
0oI2, Oatech2, etc., but preferably N
A engineering, KX, Ba engineering 2. Further, these iodine compounds may be hydrated.

The rhodium compound is usually supported on an inert phase such as activated carbon, alumina, silica, diatomaceous earth, pumice, zeolite, molecular sheep, etc., but activated carbon is particularly preferred. In this case, it is sufficient to use a supported amount of the sodium compound in the range of 0.5 to 20% by weight based on the carrier in terms of rhodium metal. The rhodium compound is supported on the carrier by a known catalyst preparation method.

The iodine compound is used by being supported on the same mK carrier as the rhodium compound. In this case, the rhodium compound may be supported simultaneously with the rhodium compound or separately, but it is advantageous to support the rhodium compound separately.

In this case, the molar ratio of the iodine compound to the rhodium compound is 1:0.01 to 1:50, preferably 1:0.1 to 1:10.

In carrying out the present invention, carbon oxide and gaseous halogenated acetic acid ester and alcohol are used as they are or diluted with an inert gas, and the mixture is introduced onto a rhodium compound catalyst to which an iodine compound is added in a gas phase. Make it react. The reactor used is a conventional fixed bed reactor used for gas phase reactions. The reaction temperature is preferably 100°C to 300°C, and the reaction proceeds under normal pressure, but it can also be carried out under slightly increased pressure.

The amounts of alcohol and carbon oxide used in the present invention are preferably in the range of 2 to 100 mol and 1 to 100 mol, respectively, per 1 mol of halogenated acetic acid. Further, the contact time of the raw material gas with the catalyst layer is preferably in the range of 0.2 to 10 seconds.

In the present invention, the reactant discharged from the reaction tube is cooled, condensed, and further distilled in accordance with a conventional method to obtain malonic acid diester.

(Example) The invention will now be explained in greater detail by way of an example.

Example 1 The catalyst was adsorbed on spherical activated carbon 10I and then further adsorbed on 10I of spherical activated carbon.The adsorbed catalyst was charged into a heat-resistant glass reaction tube with an inner diameter of 25mm and a height of 600Mk, and then heated at 250°C. -oxidized carbon X at a rate of 0.16 per hour
The mixture was introduced at a molar rate for 1 hour. - 0.20 mol of carbon oxide, methyl monochloroacetate and methanol per hour,
A mixed gas was introduced into the reaction tube through a preheater t'' maintained at 200° C. at a rate of 0.04 mol and 0.41 mol.

The reaction was carried out at a reaction temperature of 250° C. and under normal pressure.

As a result of analyzing the reaction product by gas chromatography,
Dimethyl malonate was produced at the production rate shown in Table 1.

Further, the amount of dimethyl malonate produced up to 72 hours after the start of the reaction was 670 mol/catalyst.

Table 1 Example 2 Ni 0.63, F k Na knee 2t+2o O,5
The same procedure as in Example 1 was carried out except that 7& was used.

As a result of reaction product analysis using Kegas chromatography,
Diethyl malonate was produced at the production rate shown in Table 2.The total production of dimethyl malonate up to 72 hours after the start of the reaction was 707 mol/catalyst.

2nd table fu kj reli 6 to yellow 65 ji: Ba 2" 2H201-62
The same swimming as in Example 1 was carried out except that the swimming pattern was changed to 9.

As a result of analyzing all reaction products by gas chromatography,
Dimethyl malonate was produced at the same rate of production.

Further, the production evidence of dimethyl malonate up to 72 cycles after the reaction started IA3 was 629 mol/recatalyst.

Table 6 Example 4 The same procedure as in Example 1 was carried out except that methyl monochloroacetate and methanol were used instead of ethyl monochloroacetate and ethanol, respectively. As a result of analyzing the reaction product by gas chromatography, diethyl malonate was produced at the production rate shown in Table 4. In addition, t.t/t of dimethyl malonate, or 617 mol of total dimethyl malonate, was added using one catalyst up to 72 hours after the start of the reaction.

Table 4 Example 5 Rh(so3)31! 2 whole spherical activated carbon 109]・
After this, a heat-resistant glass reaction tube with a total inner diameter of 25 mm and a height of 600 mm was charged with a catalyst adsorbed with Q, 63.9, heated to 180°C, and monotonized carbon X was added every hour. 0.1
It was introduced at a rate of 6 molar for 1 hour. Next, carbon monoxide, methyl monochloroacetate and methanol were added at 0.25 mol/hour.
A mixed gas was introduced into the reaction tube through a preheater maintained at 200° C. at a rate of 0.04 mol and 0.20 mol. The reaction was carried out at a reaction temperature of 180° C. and under normal pressure.

As a result of analyzing the reaction product by gas chromatography,
Dimethyl malonate was produced at the production rate shown in Table 5.

Further, the total amount of malonated dimethyl formed up to 72 hours after the start of the reaction was 330 mol/4-catalyst.

Table 5 Comparative Example 1 When a test was conducted using the method of Example 1 without adding KP-catalyst, the total amount of dimethyl malonate produced up to 72 hours after the start of the reaction was 441 mol/KP-catalyst. .

Comparative Example 2 A trial using the method of Example 5 without adding any additives
As a result, the total production of dimethyl malonate up to 72 hours after the start of the reaction was 216 mol/KP-catalyst.

(Effects of the invention) According to the present moxibustion method, since no basic compound is required in the gas phase, it is easy to mix the raw materials and obtain the product, and the catalytic efficiency is high and the process is simple. Malonic acid diester can be easily produced by simple operations.

Claims (1)

[Claims] 1. A method for producing a malonic acid diester, which comprises carrying out a gas phase contact reaction in the presence of an iodine compound in the reaction of a halogenated acetate, carbon monoxide, and alcohol in the presence of a rhodium compound.