JPH062760B2 - Method for producing furfuryl alcohol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention has the general formula (I) (Wherein R represents a hydrogen atom or a methyl group).

<Prior Art> Furfuryl alcohols represented by the general formula (I) are
It is a useful intermediate for agricultural chemicals, pharmaceuticals, and fragrances.

Conventionally, as a method of obtaining an alcohol by the reaction of a carbonyl compound and propargyl halide, (i) a method by a Grignard reaction, (ii) a method by Rifomasky reaction, (iii) a method through an organolithium compound, etc. are well known. ing.

However, all of these methods have the problem that they require water-prohibited conditions that are extremely disadvantageous industrially, and are extremely difficult to implement.

<Problems to be Solved by the Invention> From the above, the present inventors have improved the above-mentioned drawbacks,
As a result of various investigations for producing the furfuryl alcohols represented by the above-mentioned general formula (I) industrially, it was confirmed that furfurals and propargyl halides were reacted under specific conditions in a short time to give a full yield in good yield. The inventors have found that furyl alcohols can be obtained and have completed the present invention.

<Means for Solving Problems> That is, the present invention provides a compound represented by the general formula (II) (In the formula, R represents a hydrogen atom or a methyl group) and furfurals represented by
The present invention provides a method for producing furfuryl alcohols represented by the general formula (I), which comprises reacting in a water solvent in the presence of zinc and ammonium salts.

Furfural or 5-methylfurfural is used as the raw material furfural in the present invention.
Propargyl chloride and propargyl bromide are used as propargyl halide.

In this reaction, the amounts of propargyl halide and zinc used are preferably in the range of 1 to 2 times the moles of the furfural raw materials.

The reaction is carried out in a water solvent. The amount of water used as a solvent is usually 1 to 50 times the weight of the raw material furfural, but is not particularly limited.

As the ammonium salt coexisting in this reaction, an inorganic salt such as ammonium chloride or ammonium bromide is generally used, and the amount thereof is usually 0.05 to 1 times the weight of water as a reaction solvent. Of course, the reaction proceeds even if the weight exceeds 1 time, but the slurry concentration increases, which is industrially disadvantageous. Although the reaction proceeds even if the amount is less than 0.05 times the weight, it takes a long time to complete the reaction, which is industrially disadvantageous.

The reaction temperature is generally selected in the range of 0 to 100 ° C,
It is preferably 5 to 80 ° C.

The progress of the reaction is monitored by instrumental analysis such as gas chromatography, and the reaction ends when all the raw material furfurals have disappeared. The furfuryl alcohols are taken out from the reaction solution, for example, by separating the organic layer and then distilling the organic layer.

<Effects of the Invention> Thus, according to the method of the present invention, the desired furfuryl alcohols represented by the general formula (I) can be industrially easily obtained in a short time in a good yield.

<Examples> Hereinafter, the present invention will be described with reference to Examples.

Example 1 A flask was charged with 44 g of 5-methylfurfural, 35.8 g of propargyl halide, 31.4 g of zinc powder and 440 g of water, and then an aqueous ammonium chloride solution consisting of 95 g of ammonium chloride and 345 g of water while maintaining at 25 ± 3 ° C. under stirring. Was added dropwise over 1 hour. After the dropping was completed, the temperature was maintained for 2 hours at the same temperature.

After the reaction was completed, the reaction solution was separated, and the organic layer was rectified under reduced pressure to obtain 44.4 g (content 99.4%) of 2- (1-hydroxy-3-butynyl) -5-methylfuran fraction. (Yield 73.5
%).

Example 2 In a flask 44 g of 5-methylfurfural, 31.4 zinc powder
g, 37.1 g of ammonium chloride and 1100 g of water were charged, and 57.1 g of propargyl bromide was added dropwise over 2 hours while maintaining the temperature at 35 ± 3 ° C. with stirring. After the dropping was completed, the temperature was maintained for 2 hours at the same temperature. Thereafter, the same post-treatment as in Example 1 was carried out to obtain 46.9 g (content 99.2%) of a fraction of 2- (1-hydroxy-3-butynyl) -5-methylfuran (yield 77.5%).

Example 3 A reaction and a post-treatment were performed in the same manner as in Example 1 except that an equimolar amount of furfural was used instead of 5-methylfurfural, and 45.0 g of ammonium bromide was used instead of ammonium chloride. A fraction of 1-hydroxy-3-butynyl) -furan 39.5 gP (content 99.0%) was obtained (yield 71.8%).

Claims (1)

[Claims] 1. A general formula (In the formula, R represents a hydrogen atom or a methyl group) and furfurals represented by
General formula characterized by reacting in a water solvent in the presence of zinc and ammonium salts (In the formula, R has the same meaning as described above.) A method for producing furfuryl alcohols.