JP2005075808A - Method for producing dihalogenated adamantanes - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing dihalogenated adamantanes, capable of surely preventing a reaction from a violent progression caused by a sudden progress of the reaction in producing the dihalogenated adamantanes in performing the reaction of the adamantanes with 5-15 equivalents halosulfonic acid, and also exhibiting a higher yield than those in the case of using a metal or metal oxide. <P>SOLUTION: This method for producing the dihalogenated adamantanes is provided by adjusting reaction temperature and adding amount of the halosulfonic acid so that a state of adding the halosulfonic acid of ≥2 and ≤4 equivalents and keeping temperature at ≥17°C, is maintained for at least 2 hr in the reaction system. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing dihalogenated adamantanes useful as a raw material for functional materials and electronic materials.

  An adamantane derivative is a compound that is expected to be applied to highly functional materials such as heat-resistant polymers and electronic materials such as resists for semiconductors because of its excellent heat resistance and high transparency. Among them, dihalogenated adamantane is important as a raw material for synthesizing various adamantane derivatives having two functional groups.

  As a method of synthesizing various halogenated adamantanes from adamantane, a method of reacting a halogenated alkane in the presence of an aluminum halide (Non-patent Document 1), or a method of reacting a halogenated alkane in the presence of a cobalt salt ( Patent Document 1) has been reported. However, these methods are usually obtained as a mixture of monohalogenated compounds, dihalogenated compounds, trihalogenated compounds, etc., of which the main product is generally monohalogenated adamantane, and dihalogenated adamantane The yield of is low.

  As a method for selectively obtaining a dihalogenated adamantane, a method in which adamantane and halosulfonic acid are mixed and reacted at a temperature of 20 ° C. has been reported (for example, Non-Patent Document 2). However, in the above method, the reaction is intense at the beginning of the reaction, and when a sufficient amount of halosulfonic acid is used, the reaction is likely to proceed to the trihalide, and the dihalogenated adamantane cannot be obtained in a satisfactory yield. there were. For example, when adamantane and halosulfonic acid are charged at a molar ratio of 1: 8 and reacted for about 10 hours, the yield of dihalogenated adamantane by gas chromatography is 80% or less.

  As an improved method of the above technique, 5-15 equivalents of highly reactive chlorosulfonic acid are added to adamantane to produce 1-chloroadamantane in the range of -15 to 15 ° C, and then the temperature is raised to 17 to 35 ° C. Then, a method of converting to 1,3-dichloroadamantane by a sequential reaction has been proposed (for example, Patent Document 2). Typical values for this method improved the yield to 93% and the gas chromatographic purity to 94%. However, according to the study by the present inventors, when the sequential reaction is controlled only by the temperature, there is a risk that the reaction solution may run away at a stroke rather than sequentially due to the stirring effect due to the stirring speed or the shape of the stirring blade, and the reaction liquid may be ejected. It has been found.

  Specifically, in the reaction system, hydrogen halide and then sulfur dioxide are diffused out of the system as a gas as the reaction proceeds. If the reaction goes out of control, the monochlorination and dichloroation described above are not sequential reactions, but proceed at the same time, hydrogen halide and sulfur dioxide are generated abruptly, and it is extremely dangerous to shift to foaming of the reaction liquid, interfacial rise, and ejection. It becomes a state.

  In particular, since halosulfonic acid is a compound that has skin irritation and chemical damage and needs to be handled with great care for safety, there has been a big problem in safety.

Russian Patent Application Publication No. 21255551 (1999) JP 2003-146916 A “Synthetic Communications 19”, 1989, Vol. 9, No. 10, p. 1697-1704 “Tetrahedron Letters”, 1972, Vol. 31, p. 3191-3192

  In view of the above background, the present invention aims to provide a method for producing high yield and high purity dihalogenated adamantanes in addition to high safety under mild conditions and good workability. .

  The present inventors have intensively studied to solve the above problems. As a result, it has been found that the above-mentioned problems can be solved by adding adamantane and halosulfonic acid in two stages under specific temperature conditions, and the present invention has been completed.

  That is, the present invention is a method for producing a dihalogenated adamantane by reacting an adamantane optionally substituted at the 1-position with an alkyl group and 5 to 15 equivalents of a halosulfonic acid to the adamantane. In the reaction solution, halosulfonic acid is added in an amount of 2 equivalents or more and 4 equivalents or less with respect to the raw material adamantane, and the halosulfone is kept at 17 ° C. or more for 2 hours or more. A method for producing dihalogenated adamantanes, wherein the acid is added in portions.

  According to the present invention, since there is no runaway reaction due to sudden progress of the reaction, in addition to high safety and good workability, the yield (selectivity) is higher than when using a metal or metal salt, High yield and high purity dihalogenated adamantane can be easily produced.

  In the production method of the present invention, the adamantane used as a reaction raw material is not particularly limited as long as the adamantane skeleton can be substituted with two halogen atoms. However, the adamantane may be unsubstituted adamantane or an alkyl group at the 1-position. It is preferably an adamantane substituted with. Here, as an alkyl group, a C1-C4 linear thing, such as a methyl group, an ethyl group, a propyl group, a butyl group, is preferable, and especially a methyl group is more preferable.

The halosulfonic acid used in the production method of the present invention is
XSO ₃ H
(In the formula, X represents halogen.)
It is a compound shown by these. Examples of the halogen include fluorine, chlorine, bromine and iodine. Specific examples of the halosulfonic acid include chlorosulfonic acid, bromosulfonic acid, iodosulfonic acid and the like, and chlorosulfonic acid is particularly preferable because of its availability.

  When the amount of the halosulfonic acid used in the production method of the present invention is too small, the reaction does not proceed. When the amount is too large, polychlorination is promoted, so that it is limited to a range of 5 to 15 equivalents relative to adamantane.

  In the production method of the present invention, adihalogenated adamantane is produced by reacting adamantane (hereinafter also simply referred to as adamantanes) optionally substituted with an alkyl group at the 1-position and halosulfonic acid. Here, when the adamantane is an unsubstituted form, the dihalogenated adamantane produced is mainly 1,3-dihalogenated adamantane. Usually, in addition to the 1,3-dihalogenated adamantane, a small amount of other dihalogenated adamantane is also produced.

  On the other hand, when the adamantane is an alkyl group substituted at the 1-position, the dihalogenated adamantane produced is mainly 1-alkyl-3,5-dihalogenated adamantane. Usually, in addition to the 1-alkyl-3,5-dihalogenated adamantane, a small amount of other alkyl dihalogenated adamantane is also produced.

  Specific examples of the dihalogenated adamantane produced by the production method of the present invention include 1,3-dichloroadamantane, 1,3-dibromoadamantane, 1,3-diiodoadamantane, 1-methyl-3,5-dichloroadamantane. 1-methyl-3,5-dibromoadamantane, 1-methyl-3,5-diiodoadamantane, 1-ethyl-3,5-dichloroadamantane, 1-ethyl-3,5-dibromoadamantane, 1-ethyl- 3,5-diiodoadamantane, 1-propyl-3,5-dichloroadamantane, 1-propyl-3,5-dibromoadamantane, 1-propyl-3,5-diiodoadamantane, 1-butyl-3,5- Dichloroadamantane, 1-butyl-3,5-dibromoadamantane, 1-butyl-3,5-diiodoadaman Emissions, and the like.

  In the production method of the present invention, when an organic solvent is used, it is preferably not used because the organic solvent is halogenated or the selectivity of the target product is significantly reduced. That is, halosulfonic acid has a unique solubility property that its solubility in monohalogenated adamantane is high, while its solubility in adamantanes and dihalogenated adamantane is extremely low. Therefore, if an organic solvent is not used and halosulfonic acid as a reaction agent is also used as a reaction medium, the dihalogenated adamantane can be obtained more selectively and with high purity due to the above-mentioned specific solubility property of halosulfonic acid. Is possible. However, since adamantane has sublimation properties, it exists in a lump shape depending on the production method, and therefore there is a risk of breakage when it is put into a glass instrument or the like. Therefore, in the production method of the present invention, it is more preferable to use concentrated sulfuric acid as a solvent, which is generated by decomposing halosulfonic acid and can be expected to have the same effect as described above.

  As the concentrated sulfuric acid, commercially available reagents and industrial grades can be used without any limitation. However, since halosulfonic acid reacts with water in concentrated sulfuric acid to generate hydrogen halide, the concentration of sulfuric acid is preferably 96 to 100% by mass.

  The reaction apparatus in the production method of the present invention is not particularly limited. For example, a stirring wing connected to a mechanical power source so that the reaction system can be stirred, a thermometer, a condenser, a glass lining equipped with a vent pipe, and rubber A reaction vessel made of a lining, a fluororesin lining, or other acid-resistant material can be used.

  In the production method of the present invention, hydrogen halide and sulfur dioxide are generated due to the characteristics of the reaction. Therefore, it is better to connect an empty trap, a water trap, and an alkali trap in this order at the tip of the gas vent pipe. The reaction vessel is preferably used in a state of being immersed in a water bath or an oil bath so that the temperature can be changed, or provided with other temperature adjusting means. The agitating blade is not particularly limited, and may be appropriately selected from a fiddler blade, a meniscus blade, a turbine blade, a max blend blade, a full zone blade, an anchor blade, and the like. In the production method of the present invention, a magnetic stirrer may be used in place of the stirring blade, although it depends on the scale to be used. In this case, the shape of the stirrer piece is not particularly limited.

  The reaction mode in the production method of the present invention is a water-free reaction. For this reason, it is preferable to sufficiently dry the instrument to be used, and to sufficiently replace and dry it in advance with an inert gas such as nitrogen, argon, helium or dry air.

  In the present invention, the addition amount and time when contacting the raw material adamantanes with halosulfonic acid is the greatest feature. That is, in the production method of the present invention, halosulfonic acid is added in a divided manner to the raw material adamantane, and at this time, an amount of halosulfonic acid in an amount of 2 to 4 equivalents is added to the raw material adamantane. And the rate at which the halosulfonic acid is added must be adjusted so that the state of being maintained at 17 ° C. or higher exists for 2 hours or longer.

  In the following, the amount of added halosulfonic acid is up to 2 equivalents in the first step, the amount of halosulfonic acid is 2 to 4 equivalents, and the step that is maintained at 17 ° C. or higher for 2 hours or more is the second step, After exceeding 4 equivalents, it is referred to as the third step. In addition, in the present invention, adding halosulfonic acid in a divided manner means that the halosulfonic acid is added in a plurality of steps as described above, and does not necessarily have to be physically divided, and passes through the above steps. Thus, it may be added by a method of adding small portions continuously as a trickle.

  In the production method of the present invention, the method in the first step, that is, the step of adding less than 2 equivalents of halosulfonic acid to the raw material adamantanes is not particularly limited. A raw material adamantane (or a solution or suspension of sulfuric acid or the like) is put in such a reactor, and halosulfonic acid may be added to the reactor at once or by dropping or the like. The temperature at this time is not particularly limited, but is preferably 50 ° C. or lower, and preferably 40 ° C. or lower, in order to prevent sublimation of the raw material adamantanes. On the other hand, since there is no advantage in obtaining even lower temperatures, it is generally preferable to carry out at room temperature or higher.

  Moreover, if it is 4 equivalents or less, you may add 2 equivalents or more of halosulfonic acids at once. However, in this case, if the reaction system is 17 ° C. or higher when 2 equivalents or more are added, it corresponds to the second step described below after that point. The time required to add the amount at once is several seconds to several tens of seconds and can be ignored.

  In the production method of the present invention, a halosulfonic acid in an amount of 2 equivalents or more and 4 equivalents or less is added to the raw material adamantanes, and a state in which the halosulfonic acid is maintained at 17 ° C. or more exists for 2 hours or more. Two steps are extremely important.

  If this step is less than 17 ° C. or less than 2 hours, the reaction may run away in the subsequent third step. That is, the monohalogenation of adamantane proceeds in a state where 2 to 4 equivalents of halosulfonic acid is added to the raw material adamantane. The reaction hardly progresses, and even in less than 2 hours, the reaction does not proceed to such an extent that the runaway reaction can be completely prevented. Further, if the halosulfonic acid is less than 2 equivalents, the monohalogenation does not proceed, and if it is more than 4 equivalents, the dihalogenation also proceeds simultaneously.

  The upper limit temperature at this time is not particularly limited, but if it is too high, sublimation of adamantane occurs, so that it is preferably performed at 50 ° C. or less, more preferably 40 ° C. or less. In order to prevent runaway reaction and to efficiently proceed the monohalogenation reaction, it is preferable to perform the second step in the range of 20 to 40 ° C.

  The second step may be at least 2 hours or more, and the others are not particularly limited. However, the effect reaches a peak even if it is performed for a long time, so it is 20 hours or less, more preferably 15 hours or less. Good. In order to prevent reaction runaway more reliably and eliminate unnecessary reaction time, the second step may be performed for 2 to 20 hours, more preferably 2.5 to 15 hours.

  In this second step, even when 2 to 4 equivalents of halosulfonic acid is added to the raw material adamantane, the temperature is less than 17 ° C. Not counted. That is, for example, even when there is a state in which an amount of 2 equivalents or more and 4 equivalents or less of halosulfonic acid has been added for 3 hours, if 1.5 hours is maintained below 17 ° C., “ “A state where 2 to 4 equivalents of halosulfonic acid is added to the raw material adamantane and maintained at 17 ° C. or higher” is 1.5 (3-1.5) hours. .

  In the second step, the method of adding the halosulfonic acid is not particularly limited, and as described above, it is added at the same time as adding less than 2 equivalents of the halosulfonic acid in the first step, and then, without adding the halosulfonic acid, You may hold | maintain at 17 degreeC or more for 2 hours, After adding 2 equivalent of halosulfonic acid, you may divide | segment several times by dripping etc. and add gradually to the quantity of 4 equivalent or less, and 17 degreeC After holding for 2 hours or more as described above, it may be added so that the amount becomes 4 equivalents or more (however, it corresponds to the third step from the time when it exceeds 4 equivalents).

  In order to surely prevent runaway reaction and to reduce the labor of adding halosulfonic acid as much as possible, an amount of halosulfonic acid of 2.5 to 3.5 equivalents is added together with the addition of halosulfonic acid in the first step. Next, a method of holding at a temperature of 17 ° C. or more for 2 hours or more and then adding the remaining halosulfonic acid at a time or by adding dropwise, etc. so that the total amount of halosulfonic acid is 5 to 15 equivalents. preferable.

  As described above, the halosulfonic acid in an amount of 2 equivalents or more and 4 equivalents or less is added to the raw material adamantanes, and after being kept at 17 ° C. or more for 2 hours or more, the remainder Of halosulfonic acid is added so that the total addition amount of halosulfonic acid is 5 to 15 equivalents. At this time, if the total addition amount of halosulfonic acid to be added exceeds 15 equivalents, higher-order halogenated substances such as trihalogenated adamantane increase, while if less than 5 equivalents, the ratio of monohalogenated substances increases. In either case, the yield of dihalogenated adamantane is not sufficient.

  The reaction temperature in this third step is not particularly limited. However, if the temperature is too low, the dichloronation reaction becomes too slow and the reaction takes a very long time. On the other hand, if the temperature is too high, sublimation of adamantane occurs. Since an undesirable side reaction occurs, it is preferably performed at 17 to 70 ° C, more preferably 20 to 50 ° C. Although it depends on the reaction temperature, the reaction time is generally 1 to 300 hours, preferably 3 to 50 hours.

  Further, the reaction pressure in the production method of the present invention can be carried out under pressure, reduced pressure, or atmospheric pressure in any step.

  The change in the state of the reaction system in the present invention will be explained. When adamantanes and halosulfonic acid are charged, the reaction solution is initially in a suspended state, but after the first step, a monohalogenated adamantane is produced during the second step. Accompanying this, the reaction solution changes to a transparent homogeneous system. Further, in the third step, dihalogenation proceeds following monohalogenation, and dihalogenated adamantane is precipitated.

  As a post-treatment method of the dihalogenated adamantanes thus obtained, a known technique in halogenation using halosulfonic acid can be used without any limitation. For example, after completion of the reaction, water is added to decompose excess halosulfonic acid into hydrogen halide and concentrated sulfuric acid. The operation is preferably performed at 30 ° C. or lower because it generates heat.

  Next, the target product is extracted with an organic solvent as shown below. Examples of the organic solvent include halogenated aliphatic hydrocarbons such as methylene chloride, methylene bromide, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,2-dibromoethane, hexane, cyclohexane, heptane, octane and the like. Aliphatic hydrocarbons, aromatic hydrocarbons such as benzene, o-xylene, p-xylene, m-xylene, toluene, halogenated aroma such as chlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene Group hydrocarbons, ethyl acetate, methyl acetate, butyl acetate, isobutyl acetate, t-butyl acetate, nitriles such as acetonitrile, acetone, methyl ethyl ketone, ketones such as methyl isobutyl ketone, diethyl ether, tetrahydrofuran, t-butyl methyl ether, dimethyl Ethers such as ether and dioxane, alcohols such as methanol, ethanol, isopropyl alcohol, n-butyl alcohol, s-butyl alcohol, t-butyl alcohol, n-amyl alcohol, s-amyl alcohol, t-amyl alcohol and cyclohexanol Kind. The amount of the organic solvent used is not particularly limited. However, the amount of the organic solvent is 1 to 100 times the weight of the adamantane because the reactant is sufficiently dissolved and the yield of the kettle is not significantly reduced. It is good to select suitably according to the reaction system from the inside.

  Further, after washing with a 0.1 to 10N aqueous sodium hydroxide solution and then with a 0.1 to 20% by mass aqueous sodium sulfate solution, the organic solvent is distilled off to isolate the desired product. The isolation operation may be carried out as it is, may be recrystallized, or may be isolated by crystallization or reprecipitation. For this isolation operation, a known technique can be used without any limitation. Examples include decantation, pressure filtration, vacuum filtration, and centrifugal filtration.

  The dihalogenated adamantane thus obtained can be dried by a known method. For example, vacuum drying, freeze drying, air drying, warm air drying, humidity drying and the like can be performed at low temperature, room temperature, and high temperature.

  The dihalogenated adamantanes obtained by such a method are converted to adamantanediol by hydrolysis or the like, and diaminoadamantanes by ammonolysis or the like, so that functional materials such as heat-resistant polymers and electronic materials such as resists are obtained. It can be used effectively as a raw material.

  EXAMPLES Hereinafter, although an Example is given and this invention is described still in detail, this invention is not restrict | limited at all by these Examples.

Example 1
100 g of 98 mass% concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 1000 ml three-necked flask and dried through nitrogen gas. Next, the temperature was adjusted to 30 ° C. while the nitrogen was flowing by switching to a T-tube, and 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was added dropwise over 45 minutes (15 minutes / equivalent). After completion of the dropwise addition, the mixture was stirred for 3 hours while maintaining the temperature at 30 ° C. Thereafter, 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was added dropwise at 35 ° C. over 45 minutes (15 minutes / equivalent), and the stirring was stopped after stirring for 10 hours. Step 2 in this reaction was a total of 3 hours and 30 minutes, and only a slight foaming was observed in the reaction solution. After the reaction, the reaction solution was cooled to 10 ° C. or less, and 100 g of water was added dropwise. Further, 200 g of methylene chloride was added, the target product was extracted, washed with 100 g of 5N sodium hydroxide aqueous solution and 200 g of 20% sodium sulfate aqueous solution, and then methylene chloride was distilled off. 1,3-dichloroadamantane was obtained in a yield of 70 g, a yield of 93%, and a GC purity of 94%.

Comparative Example 1
100 g of 98% by weight concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 1000 ml three-necked flask and dried through nitrogen gas. Next, the temperature was lowered to 0 ° C. while nitrogen was flowing while switching to a T-shaped tube, and 431 g (3.7 mol, 10 equivalents) of chlorosulfonic acid was added dropwise over 150 minutes (15 minutes / equivalent). When the temperature of the suspended reaction solution was raised to 10 ° C. to start the monochromation reaction, foaming started. When the temperature was maintained until foaming subsided, the solution became a transparent homogeneous solution after 2 hours.

  When the temperature was raised to 20 ° C. and the dichloronation reaction was started, the reaction solution gradually rose and spouted. As a result, the reaction solution could not be quantified and analyzed.

Comparative Example 2
100 g of 98 mass% concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 1000 ml three-necked flask and dried through nitrogen gas. Next, the temperature was adjusted to 10 ° C. while the nitrogen flow was performed by switching to a T-tube, and 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was maintained for 45 minutes (15 minutes / equivalent). It was dripped over. After completion of dropping, the mixture was stirred for 3 hours while maintaining the temperature at 10 ° C. At this time, the reaction solution has hardly changed. Thereafter, 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was added dropwise at 10 ° C. over 45 minutes (15 minutes / equivalent), and after 1 hour, when the temperature was raised to 25 ° C., the reaction solution was vigorously foamed and ejected. . As a result, the reaction solution could not be quantified and analyzed.
Comparative Example 3
100 g of 98 mass% concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 100 ml three-necked flask and dried through nitrogen gas. Next, the temperature was adjusted to 25 ° C. while flowing nitrogen by switching to a T-tube, and 43 g (0.37 mol, 1 equivalent) of chlorosulfonic acid was added dropwise over 15 minutes while maintaining the temperature (15 Min / equivalent). After completion of dropping, the mixture was stirred for 3 hours while maintaining the temperature at 25 ° C. At this time, the slurry concentration slightly decreased in the reaction solution. Thereafter, when 215 g (1.85 mol, 5 equivalents) of chlorosulfonic acid was added dropwise at 30 ° C. over 75 minutes (15 minutes / equivalent), the reaction solution was vigorously foamed and ejected. As a result, the reaction solution could not be quantified and analyzed.
Example 2
100 g of 98 mass% concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 1000 ml three-necked flask and dried through nitrogen gas. Next, the temperature was adjusted to 20 ° C. while the flow was changed to a T-tube and nitrogen was flowing, and 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was added dropwise over 30 minutes (30 minutes / equivalent). After completion of the dropwise addition, the temperature was raised to 30 ° C. and the mixture was stirred for 1 hour. Thereafter, 172 g (1.48 mol, 4 equivalents) of chlorosulfonic acid was added dropwise at 35 ° C. over 2 hours (30 minutes / equivalent), and reacted for 5 hours. Step 2 in this reaction was 2 hours in total, and the foaming of the reaction solution was only slightly observed. After the reaction, the reaction solution was cooled to 10 ° C. or less, and 100 g of water was added dropwise. Further, 200 g of methylene chloride was added, the target product was extracted, washed with 100 g of 5N sodium hydroxide aqueous solution and 200 g of 20% sodium sulfate aqueous solution, and then methylene chloride was distilled off. 1,3-dichloroadamantane was obtained in a yield of 70 g, a yield of 93%, and a GC purity of 95%.

Comparative Example 4
Example 2 was followed except that the amount of chlorosulfonic acid in the first round was changed to 258 g (2.22 mol, 6 equivalents). Ten minutes after the completion of the first addition of chlorosulfonic acid, the reaction solution was vigorously foamed and ejected. As a result, the reaction solution could not be quantified and analyzed.

Comparative Example 5
Example 2 was followed except that the amount of chlorosulfonic acid added in the second time in Example 2 was changed to 645 g (5.5 mol, 15 equivalents, total 18 equivalents). 1,3-dichloroadamantane was obtained in a yield of 70 g, a yield of 93%, and a GC purity of 75%. The reason why the GC purity is low is that the trichloro form was by-produced by 20%.

Example 3
100 g of 98 mass% concentrated sulfuric acid and 50 g (0.37 mol) of adamantane were placed in a 1000 ml three-necked flask and dried through nitrogen gas. Next, the temperature was adjusted to 30 ° C. while nitrogen was flowing while switching to a T-shaped tube, and 172 g (1.48 mol, 4 equivalents) of chlorosulfonic acid was added at once. After the addition, when the mixture was stirred for 4 hours while maintaining the temperature at 30 ° C., a slight solid remained, but it turned almost uniform and transparent. Thereafter, the temperature was raised to 40 ° C. and 129 g (1.11 mol, 3 equivalents) of chlorosulfonic acid was added all at once, and stirring was stopped after stirring for 20 hours. Step 2 in this reaction was 4 hours, and the foaming of the reaction solution was only slightly observed. After the reaction, the reaction solution was cooled to 10 ° C. or less, and 100 g of water was added dropwise. Further, 200 g of methylene chloride was added, the target product was extracted, washed with 100 g of 5N sodium hydroxide aqueous solution and 200 g of 20% sodium sulfate aqueous solution, and then methylene chloride was distilled off. 1,3-dichloroadamantane was obtained in a yield of 70 g, a yield of 93%, and a GC purity of 95%.

  The figures showing the reaction times in these Examples and Comparative Examples and the amount of halosulfonic acid added to the reaction system (equivalent to the raw material adamantanes) are shown as FIGS. 1 to 7 (however, basically 6 hours). Omitted after eye). As can be seen from these figures, in order to prevent runaway of the reaction, “a halosulfonic acid in an amount of 2 equivalents or more and 4 equivalents or less is added to the raw material adamantane, and the reaction temperature is 17 ° C. or more. It is necessary to adjust the reaction temperature and the amount of halosulfonic acid added so that the "held state" is at least 2 hours.

The figure which shows the quantity of the halosulfonic acid added to reaction time and the reaction system in Example 1. FIG. The figure which shows the quantity of the halosulfonic acid added to the reaction time in Example 2, and the reaction system. The figure which shows the quantity of the halosulfonic acid added to the reaction time in Example 3, and the reaction system. The figure which shows the quantity of the halosulfonic acid added to the reaction time and reaction system in the comparative example 1. The figure which shows the quantity of the halosulfonic acid added to the reaction time and reaction system in the comparative example 2. The figure which shows the quantity of the halosulfonic acid added to the reaction time and reaction system in the comparative example 3. The figure which shows the quantity of the halosulfonic acid added to the reaction time and reaction system in the comparative example 4.

Claims (3)

A method of producing a dihalogenated adamantane by reacting an adamantane optionally substituted with an alkyl group at the 1-position with 5 to 15 equivalents of a halosulfonic acid to the adamantane, 2 to 4 equivalents of halosulfonic acid is added to the raw material adamantane, and the halosulfonic acid is added in portions so that a state of being maintained at 17 ° C. or more exists for 2 hours or more. A process for producing dihalogenated adamantanes, characterized in that The process according to claim 1, wherein the reaction is carried out in the absence of an organic solvent. The process according to claim 1 or 2, wherein the reaction is carried out using concentrated sulfuric acid as a solvent.

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