JPS6025416B2 - Method for producing 9,10-secodehydroabietic acid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing 9,10-secodehydroapietic acid represented by formula (1).

9,10-Secodehydroabietic acid has a unique structure, and although it has the same molecular weight as abietic acid, it is more stable against oxidation than abietic acid, and the surface activity of its alkaline salt is higher than that of other abietic acids. Although it is not different from alkali salts of resin acids, it has excellent solubility in water, so it can be expected to have unique uses as a surfactant, and because of its structure, it can also be used as a plasticizer, lubricant, etc. However, the object of the present invention is to provide a method for producing 9,10-secodehydroabietic acid with easy operations and a good yield.

Further, the present invention aims to provide an economical method for purifying 9,10-secodehydroabietic acid.

Generally, rosin that exists as a natural product is mainly composed of a carboxylic acid derivative of hydrogenated phenanthrene called resin acid, but this rosin includes gum rosin obtained from raw pine resin and tall oil obtained from pulp waste liquid Examples include tall oil rosin, which is obtained by separating the resin acid content therein by distillation, and wood rosin, which is obtained by extracting from pine wood.

Resin acids, which are the main components of rosin, are classified into abietic acid, pimaric acid, and isopimaric acid based on their structure, but abietic acid resin acids include abietic acid and isomers of abietic acid. These include parastophosphoric acid, neoapietic acid, and levopimaric acid. However, rosin contains almost no derivatives of cyclohexanecarboxylic acid, which has a structure in which a carboxyl group is attached to the cyclohexane ring, such as 9,10-secodehydroapietic acid shown by formula (1). do not have.

On the other hand, it is known that the above-mentioned cyclohexanecarboxylic acid derivatives can be produced by organic synthesis reactions from petrochemical products or other chemicals, but this method requires multiple reaction routes and is economically undesirable. It's profit.

However, according to the method of the present invention, which is characterized in that 0.1 to 10% by weight of 1,1'-dithiodi-2-naphthol is added to abietic acid or rosin and heated, the above-mentioned cyclohexanecarboxylic acid structure 9,10-Secodehydroabietic acid represented by the formula (1) can be produced in a good yield in a one-step reaction by relatively simple operations.

As is well known, apietic acid or rosin used in the present invention is easily available as a natural product. The 1,1'-dithiodi-2-naphthol used as a catalyst was prepared using a method according to German Patent No. 611144.
It can be easily synthesized using S, S, NaOH and 8-naphthol as raw materials.

The reaction in the present invention is easy to operate, and 0.1
By adding ~10% by weight of the above 1,1'-dithiodi-2-naphthol to abietic acid or rosin and heating at a temperature of 25,000 or less, preferably around 200q○, 50 to 55% by weight of 9 to abietic acid is added.・10-
Secodehydroabietic acid is produced.

At the time when abietic acid disappears, in addition to 9,10-secodehydroabietic acid, dehydroabietic acid power 20
-25 wt% and 10-15 M% of deisopropyl dehydroabietic acid. The amount of 1,1'-dithiodi-2naphthol added is 0.1 to 1 based on experimental results.
% by weight. These mixtures can be purified by various methods, but in the present invention, distillation was adopted as the most economical method. That is, by fractionating by vacuum distillation, crab components with a relatively low boiling point are removed, and a mixture of 9,10-secodehydroabietic acid and 15 to 2% deisopropyl dehydroabietic acid is obtained. Obtained. That is, 9,10-secodehydroapietic acid was purified to a purity of 75-80%. The mixture of 9,10-secodehydroabietic acid, dehydroabietic acid and disopropyl dehydroabietic acid before distillation purification exhibits some fluidity at room temperature, The mixture of 9,10-secodehydroabietic acid and disopropyl dehydroabietic acid obtained by distillation purification becomes a viscous liquid.

As mentioned at the beginning of this specification, this 9,10-secodehydroabietic acid is expected to have unique uses as a surfactant, and is also a useful substance that is expected to be used as a plasticizer and lubricant. It is.

Specific examples of the present invention will be illustrated below.

Example 1 To 10 liters of abietic acid, 1 part of 1,1'-dithio-di-2-naphthol was added, and after raising the temperature to 20,000 ℃, the composition of the reactant was monitored at each time.

Gas chromatography was used for compositional analysis. The analysis results are shown in Table-1. Secodehydroabietic acid appears as two isomers in gas chromatography, and is shown in Table 1 as the sum of the two isomers. -Table- [(All values are expressed in area measured by gas chromatography.

) Example 2 Reaction mixture obtained in Example 1 50
Distillation was carried out under reduced pressure using a 400 mm tall clay tower filled with a filler.

The results are shown in the table below. Furthermore, during the first distillation 9.10
- The mixture of fractions rich in secodehydroabietic acid (■, ■) was rectified again. The results are shown in Table m. Table-U ■+■ 39.7wt* (yield) Table-m The yield is shown as the value when the mixture of honey components ■ and ■ in Table-0 is taken as 100 units.

Claims (1)

[Claims] 1. A method for producing 9,10-secodehydroabietic acid, which comprises adding 0.1 to 110% by weight of 1,1'-dithio-di-2-naphthol to abietic acid or rosin and heating the mixture.