JP2009062342A - Selection method of solvent for nitration of solid organic compound, and nitration reaction method of substrate organic compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a selection method of a solvent for nitration of a solid organic compound, and a nitration reaction method of a substrate organic compound. <P>SOLUTION: The selection method of a solvent for nitration of a substrate organic compound, used for a nitration reaction method where a nitration reaction of a substrate organic compound is carried out by employing nitric acid as a nitrogen source in a reaction site of high-temperature high-pressure water and using a microtube continuous reaction apparatus for a nitric acid-resistant environment, comprises selecting a solvent by comparing a nitration temperature range of the substrate with the nitration temperature range of the solvent and by utilizing the difference of the temperature ranges between them. The nitration reaction method of the substrate organic compound comprises effecting a nitration reaction of the substrate organic compound by employing nitric acid as a nitrogen source in a reaction site of high-temperature high-pressure water and using a microtube continuous reaction apparatus for a nitric acid-resistant environment, where the nitration reaction of the substrate organic compound is carried out by using the solvent for nitration selected by the method above. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for selecting a nitration solvent for a solid organic compound and a nitration reaction method for a substrate organic compound. More specifically, the present invention relates to a nitration reaction of a substrate to be nitrated in a nitration reaction in an environment of high-temperature high-pressure water. Characterized by distinguishing and selecting the solvent to be used by comparing the nitrating temperature region and the nitrating temperature region of the solvent, and thereby improving the yield and selectivity of the nitro compound. The present invention relates to a method for selecting a nitrating solvent for a solid organic compound in a nitration reaction under an environment of the above, and a nitration reaction method capable of improving the yield and selectivity of the nitro compound.

  In addition to uses such as explosives, nitro compounds are important starting materials for a wide range of organic industrial products such as dyes and pharmaceuticals as amine derivatives by reduction. In fact, the consumption of nitro compounds worldwide is enormous (Non-patent Document 1). In the present industrial synthesis of nitro compounds, Mitscherich's nitration method (Non-patent Document 2) has been adopted as a practical method. Since nitration reaction often shows the behavior of strong exothermic reaction, there is inherent danger such as explosion accidents in industrial processes (Non-patent Document 3), and this is conventionally the reaction in nitration processes. It is recognized as a serious problem in control technology.

  To date, the inventors have shown that a micro reaction field with a small reaction volume in a high-temperature, high-pressure water field can minimize the risk of reaction runaway, and the micro-reactor can achieve efficient heat transfer and mixing. Since it is possible to control the reaction smoothly, research has been conducted as an organic synthesis field. Furthermore, we have developed a continuous microtube reactor for nitric acid resistant environment, and have developed a synthesis method of nitrobenzene from benzene by nitration reaction in high temperature and high pressure water.

  Compounds that are the raw materials for the most economically important aromatic nitro compounds as organic industrial products, for example, naphthalene is a solid with a melting point of 80 ° C., and 1-nitronaphthalene is a chemical product such as pharmaceuticals, agricultural chemicals, and pigments. Used as a raw material.

  In order to feed naphthalene as a substrate into a high-temperature and high-pressure water environment, a high-pressure pump for liquid introduction generally used cannot supply naphthalene as a crystalline solid. Generally, in such a case, the object is achieved by dissolving the substrate in a solvent. FIG. 1 shows a schematic diagram when naphthalene developed by the present inventors is dissolved in n-hexane and fed into a nitration reaction system of high-temperature high-pressure water.

  However, the present inventors have clarified that there are cases where the oxidative decomposition or nitration of the solvent proceeds in the nitration reaction in the environment of high-temperature and high-pressure water. That is, when the solvent used for the nitration reaction is nitrated, both the yield and selectivity of the original nitro compound are greatly reduced, and the nitrogen source is reduced.

  Accordingly, it is necessary to select a solvent that is not nitrated as the solvent used in the nitration reaction in the environment of high-temperature and high-pressure water. At the same time, the solvent is required not to cause damage to the reactor or third toxic substances (such as dioxins).

Industrial Commodity Statistics Yearbook 1995, United Nations, New York, (1997) Mitscherich,. Annln. Phys. Chem. 31, 625-631, (1834) A. Lunghi, P Cardillo, Riv. Combust. 51, 1 (1997)

  Under such circumstances, in view of the above prior art, the present inventors, in nitration reaction under the environment of high temperature and high pressure water, do not reduce the yield and selectivity of the target nitro compound. As a result of accumulating extensive research with the goal of developing a nitrification reaction method, it is possible to compare the nitration temperature region of the substrate with the nitration temperature region of the solvent, and identify and select the solvent used in the nitration reaction. The inventors have found that the purpose of the period can be achieved and have completed the present invention.

  The present inventors have discovered and completed an appropriate solvent discrimination method using the nitration reaction temperature zone in the process of conducting the nitration reaction in the environment of high-temperature and high-pressure water from such a viewpoint. It has come to be done. In particular, the present invention aims to provide a method for selecting a nitration solvent for a solid organic compound and a nitration reaction method for improving the yield and selectivity of a nitro compound in a nitration reaction system of high-temperature and high-pressure water. It is.

The present invention for solving the above-described problems comprises the following technical means.
(1) To be used in a nitration reaction method in which nitration of a substrate organic compound is carried out using nitric acid as a nitrogen source and a microtube continuous reaction apparatus for nitric acid resistant environment in a reaction field of high-temperature high-pressure water. The method of selecting the nitration solvent for the substrate organic compound, comparing the nitration temperature region of the substrate with the nitration temperature region of the solvent, and selecting the solvent using the difference between the temperature regions of the two A method for selecting a nitration solvent for a substrate organic compound, characterized by:
(2) The method for selecting a nitration solvent according to the above (1), wherein the reaction field of the high-temperature high-pressure water is a micro-reaction field with a small reaction volume.
(3) The method for selecting a nitration solvent according to the above (1), wherein the nitration reaction of the substrate organic compound is performed using a microtube continuous reaction apparatus for nitric acid resistant environment in the presence of dilute nitric acid.
(4) The method for selecting a nitration solvent according to (1), wherein the temperature and pressure conditions of the high-temperature and high-pressure water are 200 to 400 ° C. and 25 to 40 MPa, respectively.
(5) As a microtube continuous reactor for nitric acid-resistant environment, a microtube reactor installed in an oven that can be maintained at a set temperature, a supply device that supplies a high-temperature high-pressure water nitrogen source reagent and a substrate to the reactor, A structure in which a continuous reaction system is constructed by connecting at least a high-pressure pump for carrier water feeding, nitrogen source reagent introduction and substrate introduction, and a cooling device for cooling the reaction product through a piping system so that continuous reaction is possible. The nitration solvent selection method according to the above (1), wherein the nitration reaction of the substrate organic compound is performed using a microtube continuous reaction apparatus for a nitric acid resistant environment characterized by having.
(6) In the nitration reaction method of performing nitration reaction of a substrate organic compound using a microtube continuous reaction apparatus for nitric acid resistant environment using nitric acid as a nitrogen source in a reaction field of high-temperature high-pressure water, A method for nitration of a substrate organic compound, wherein the nitration reaction of the substrate organic compound is performed using the nitration solvent selected by the method according to any one of 1) to (5).
(7) The method for nitration reaction of a substrate organic compound according to (6), wherein the yield and selectivity of the target nitro compound are improved by the nitration reaction method.

Next, the present invention will be described in more detail.
The present invention is used in a nitration reaction method in which nitration of a substrate organic compound is performed using a microtube continuous reaction apparatus for nitric acid resistant environment using nitric acid as a nitrogen source in a reaction field of high-temperature high-pressure water. A method for selecting a nitration solvent for a substrate organic compound, comparing the nitration temperature region of the substrate with the nitration temperature region of the solvent, and selecting the solvent using the difference between the temperature regions of the two It is characterized by this.

  In the present invention, the reaction field of the high-temperature high-pressure water is a micro-reaction field with a small reaction volume, and the nitration reaction of the substrate organic compound is performed using a micro-tube continuous reaction apparatus for nitric acid resistant environment in the presence of dilute nitric acid. That is, the temperature and pressure conditions of the high-temperature and high-pressure water are 200 to 400 ° C. and 25 to 40 MPa, respectively.

  Further, in the present invention, as a microtube continuous reactor for nitric acid-resistant environment, a microtube reactor installed in an oven that can be maintained at a set temperature, and a supply of nitrogen source reagent and substrate with high-temperature and high-pressure water to the reactor A continuous reaction system is configured by connecting the equipment, at least a carrier water feed, a high-pressure pump for introducing a nitrogen source reagent and a substrate, and a cooling device for cooling a reaction product through a piping system so that the reaction product can be continuously reacted. In a preferred embodiment, the nitration reaction of the substrate organic compound is performed using a continuous microtube for nitric acid resistant environment characterized by having the above structure.

  Furthermore, the present invention provides a nitration reaction method in which nitration of a substrate organic compound is carried out using a microtube continuous reaction apparatus for nitric acid resistant environment using nitric acid as a nitrogen source in a reaction field of high-temperature high-pressure water. The nitration reaction of the substrate organic compound is carried out using the nitration solvent selected by the above method.

  Usually, the liquid substrate is injected into the environment of high-temperature and high-pressure water by a high-pressure pump. The crystal is dissolved in a solvent and the same operation is performed. The method for selecting a substrate solvent for the nitration reaction of the present invention selects a suitable nitration solvent for the nitration reaction using the difference between the temperature range of the substrate nitration reaction and the temperature range of the solvent nitration reaction. To do. This is specifically shown below with an example of naphthalene.

  Regarding the nitration temperature region of the substrate and the nitration temperature region of the solvent, the present inventors have proposed that as the solvent for solubilizing naphthalene, acetonitrile, acetone, chloroform, etc. undergo gas decomposition of the solvent, and the original nitration Has been found through research. On the other hand, assuming that hexane is used as a solvent (solubility is limited to about 8.9 w / w%), when hexane is subjected to a nitration reaction, nitrohexane is produced (FIG. 2). In fact, when performing nitration of naphthalene using hexane as a solvent, a mixture of nitrohexane and nitronaphthalene is analyzed (FIG. 3).

  Therefore, when nitrobenzene is used as a solvent, the nitration temperature of nitrobenzene and the nitration temperature range of naphthalene are different, and in this case, the comparison shows that it is the best nitration solvent (FIG. 4). . Therefore, when selecting the solvent of the solid substance to be nitrated, it is possible to select whether or not it is a suitable solvent by finding the nitration temperature zone of the solvent in advance. The present invention provides a substrate organic compound nitration reaction method in which the nitration reaction of the substrate organic compound is performed using the nitration solvent selected by the above method. Since the method of the present invention is characterized by selecting a nitration solvent compatible with the substrate organic compound to be used, the method of the present invention can be applied without being limited to the kind of the substrate organic compound. Is.

The present invention has the following effects.
(1) In the nitration reaction method of the substrate organic compound in the environment of high temperature and high pressure water, the yield and selectivity of the target nitro compound can be remarkably improved.
(2) A nitration reaction method capable of improving the yield and selectivity of a nitro compound obtained in a reaction field of high-temperature and high-pressure water can be provided.
(3) A production system using a new nitration reaction method using high-temperature and high-pressure water can be constructed and provided.
(4) When a solid solvent to be nitrated is selected, a suitable solvent can be found by previously comparing the nitration temperature zone of the substrate with the nitration temperature zone of the solvent.
(5) A decrease in the yield and selectivity of the nitro compound and a decrease in the nitrogen source can be effectively prevented.

  EXAMPLES Next, although this invention is demonstrated concretely based on an Example, this invention is not limited at all by the following Examples.

In this example, a nitric acid resistant environment microtube continuous reaction apparatus was constructed and produced.
High-pressure pump; 0.001 to 100 ml / min (ISCO260D continuous liquid feeding system) for carrier water feeding (1), water washing and dilution adjustment (2), nitrogen source reagent introduction (3), substrate The pump for introduction (4) and the liquid phase-homogenizing solvent (5) were used. In addition, as shown in FIG. 5, high-temperature high-pressure water supply device (6); 400 ° C / 40 MPa high-temperature high-pressure water 20 ml / min supply capacity, microtube reactor (7); outer diameter 1/16 inch titanium lining A pipe, an inner diameter of 0.5 mm, a length of 1 m, a cooling device (8); a heat exchanging capacity of high-temperature water of 20 ° C / 40 MPa from high-temperature high-pressure water of 400 ° C / 40 MPa was installed.

  High pressure conditions are 25 to 40 MPa (± 0.02 MPa), ER3000 system (manufactured by Tescom), electronic balance (10); ability to constantly monitor flow rate, safety device (11); operating at 60 MPa (MAX), Temperature measurement means (12): an outer diameter 1/16 inch sheath thermocouple, measurement range of 10 to 600 ° C. (± 0.5 ° C.) was installed.

  The piping system was all composed of the same connecting parts as the 1/16 inch titanium lining pipe, and a check valve and a stop valve were provided as necessary. The microtube reactor was configured in an oven apparatus that could be maintained at the experimental operating temperature.

  In this example, the nitration temperature zone of hexane for use as a dilute solvent for naphthalene was confirmed. As reagents used, n-hexane, acetone (Wako Pure Chemical Industries, Ltd.), and ultrapure water were used. The reaction temperature and reaction pressure conditions were 200-400 ° C. and 40 MPa, respectively. Each high-pressure pump (1), (2), high-temperature high-pressure water supply device (6), cooling device (8), pressure control device (9), electronic balance (10), temperature measuring means (12), micro tube reactor (7) After confirming normal connection of the oven and the piping system, it was confirmed that there was no leakage at the experimental pressure (confirmed normal operation of the pressure control device (9)). Then, after confirming the normal operation of the cooling device (8), confirm the normal operation of the high-temperature and high-pressure water supply device (6), confirm the normal operation of the oven, and finally the amount of water introduced by each pump Was confirmed with an electronic balance (10), and then set to experimental conditions.

  In the experiment, the pump (1) feed rate was 5 ml / min, (3) nitric acid (3 N) feed rate was 2 ml / min, (4) hexane feed rate was 0.5 ml / min, and (5) More acetone was introduced at a rate of 10 ml / min for a liquid-phase-homogenizing solvent. The experimental section of 200-400 ° C was cooled to 25 ° C or lower by the cooling device (8). Samples were taken at the same temperature at the inlet and outlet of the microtube reactor. Table 1 shows values set by experiments using a microtube continuous reaction apparatus for a nitric acid resistant environment for the optimum temperature zone in the hexane nitration reaction.

  The results of the nitration reaction performed under these conditions are shown in FIG. 6 by GC analysis chromatography. In this nitration reaction, 3-nitrohexane, 2-nitrohexane and 1-nitrohexane were synthesized. Among them, 3-nitrohexane and 2-nitrohexane are the main components. FIG. 7 shows the total nitrohexane yield and temperature zone in this reaction. It has been found that the temperature range in which hexane is nitrated mainly ranges from 250 ° C to 400 ° C.

  In this example, nitro compounds produced when naphthalene was introduced with a hexane solvent were examined. Nitration of naphthalene diluted with hexane (8.85 w / w%) was similarly carried out in a microtube continuous reactor for nitric acid resistant environment. However, the reaction temperature was 200-400 ° C. The conditions are shown in Table 2.

  The results of GC analysis of the nitration reaction product performed under these conditions are shown in FIG. In this nitration reaction, hexane was nitrated and converted to 3-nitrohexane, 2-nitrohexane and 1-nitrohexane. Similarly, naphthalene is nitrated and converted to 1-nitronaphthalene and trace amounts of 2-nitronaphthalene, resulting in a synthesized mixture. As a result, it was found that the yield and selectivity of nitronaphthalene are greatly reduced.

  FIG. 9 shows the yield and temperature zone of total hexane nitrate and total naphthalene nitrate in this reaction. The temperature range in which hexane is nitrated is 250 ° C. to 400 ° C., the temperature range of naphthalene is in the range of 225 to 400 ° C., and the high yield nitration regions of both are widely overlapped. From these results, it can be seen that hexane is not suitable for the nitration reaction in a high temperature and high pressure water environment as a substrate solvent for nitration.

  The results in the case of hexane solvent are shown in Table 3. Each component of the reaction effluent was summarized in grams of material per liter of 0.032M naphthalene. The molar yield of nitrohexane was obtained by multiplying the total number of moles of 3-nitrohexane, 2-nitrohexane and 1-nitrohexane by the number of moles of naphthalene supplied. Nitronaphthalene was treated in the same manner.

  In this example, the nitration temperature region of nitrobenzene was examined. The experiment confirmed whether the dilute solvent of naphthalene and the nitration temperature region of nitrobenzene did not overlap. Nitrobenzene was similarly nitrated in a microtube continuous reactor for nitric acid resistant environments. However, the reaction temperature was 200-400 ° C. The conditions are shown in Table 4 and FIG.

  As a result, it can be seen that the temperature at which the nitration reaction of nitrobenzene begins to proceed is 350 ° C. or later, and has a temperature range where the highest yield of naphthalene starts around 250 ° C. and an opening of about 100 ° C.

  Further, the solubility of naphthalene in hexane is about 8.9 w / w% at room temperature, whereas nitrobenzene has a high solubility (30 w / w% or more). This has a great advantage in increasing the production efficiency of nitronaphthalene.

  In this example, we tried to nitrate naphthalene by diluting nitrobenzene. Table 4 shows the settings when nitrobenzene was used as the nitrating solvent for naphthalene. The naphthalene concentration of naphthalene / nitrobenzene is 25 w / w%. The result is shown in FIG.

  As is apparent from the figure, nitrobenzene is not nitrated but only naphthalene is nitrated to produce nitronaphthalene. In this experiment, naphthalene is completely converted into a nitro compound in a temperature range of about 225 to 250 ° C. Thus, when selecting a solvent for a crystalline organic compound such as naphthalene, an appropriate solvent for the nitration reaction can be selected by examining the nitration temperature zone.

  The results for the nitrobenzene solvent are shown in Table 5. Each component of the reaction effluent was summarized in grams of material per liter of 0.292 M naphthalene. The molar yield of each nitronaphthalene was obtained by multiplying the number of moles of 1-nitronaphthalene and 2-nitronaphthalene produced at each temperature by the number of moles of naphthalene supplied.

The structure of the synthetic nitro compound was identified as follows.
(1) Analytical instrument used for analysis of nitrated organic compound The following analytical instrument was used.
A. GC-MS analyzer: A-1; HP6890 GC System + 5973 Mass Selective Detector. A-2: JMS manufactured by JEOL Ltd. 700
B. GC analyzer: Agilent Technologies 6890N Network GC System.
C. NMR analyzer: Varian Innova 300
D. IR analyzer: Nicole Magna 560 (in KBr or liquid film)
E. High performance liquid chromatography (HPLC): Agilent 1100 HPLC
F. Structural analysis database: F-1; Spectral database of organic compounds; National Institute of Advanced Industrial Science and Technology (Spectral Data Base System) (SDBS); F-2; Wiley 275 Data Base

The structure of 1-nitronaphthalene and 2-nitronaphthalene synthesized in the present invention was determined as follows.
(2) Case of hexane solvent FIG. 12 shows the GC analysis results of the reaction solution at 300 ° C./40 MPa. Major peaks associated with the nitro compound, 3.96, 4.19, 4.80, 6.24, 9.25, and 9.50 were identified. 6.24 has been confirmed to be naphthalene as a raw material.

1) With respect to the peak having a retention time of 9.25, it was determined as 1-nitronaphthalene by the following procedure.
The reaction solution was analyzed by A-1, and the structure of 1-nitronaphthalene was supported by the structural analysis database: F-2 with a concordance rate of 95% from the mass cleavage pattern. The comparison chart is shown in FIG.

  Next, the corresponding fraction from the reaction solution was always confirmed by GC analysis B, and fractionated by column chromatography. The obtained yellow crystals having a melting point of 60 ° C. were determined to be 1-nitronaphthalene because they were completely in agreement with IR analysis, known samples, and infrared spectrum data of Base System (SDBS) in AIST (FIG. 14). ).

2) With respect to the peak having a retention time of 9.50, it was determined as 2-nitronaphthalene by the following procedure.
The reaction solution was analyzed by A-1, and the structure of 2-nitronaphthalene was supported by the structural analysis database F-2 with a concordance rate of 95% from the mass cleavage pattern. The comparison chart is shown in FIG.

  Next, the corresponding fraction from the reaction solution was always confirmed by GC analysis B and fractionated by column chromatography. The obtained crystal having a melting point of 79 ° C. was determined to be 2-nitronaphthalene because it was completely matched as a result of comparison with IR analysis, known samples, and infrared spectrum data of Base System (SDBS) in AIST (FIG. 16). .

(Hexane nitro compound)
3) For the three peaks with retention times of 3.96, 4.19, and 4.80, all of them have the molecular formula C ₆ H ₁₃ NO ₂ , molecular weight 131 by n-mass (A-2), It was determined to be a nitro compound.
Next, the peak assignment was determined by fractionating the three components (3.96, 4.19, and 4.80) by HPLC (E) and IR (D), NMR method (C).

  The peak at a retention time of 4.80 was determined to be 1-nitrohexane because it was completely matched as a result of comparison with the infrared spectrum data of known substances and Spectral Data Base System (SDBS) in AIST (Fig. 17).

The peak of retention time 4.19 is a nitro compound of molecular formula C ₆ H ₁₃ NO ₂ , molecular weight 131 and n-hexane according to minimass (A-2), and therefore according to NMR method (C), A4.57 (J = 6.97), B1.91 (J = 7.32), C1.72 (J = 7.45), D1.29, E1.25, F0.91 (J = 7.57) absorption From the spectrum and ChemNMR 1H Estimate (ChemDraw), the structural formula was determined as the following 2-nitrohexane. The structural formula is shown below, and FIG. 18 shows the NMR data.

The peak of retention time 3.96 is a nitro compound of molecular formula C ₆ H ₁₃ NO ₂ , molecular weight 131 and n-hexane according to minimass (A-2). Therefore, according to NMR method (C), A 4. 41 (J = 4.65 Hz), B 1.97 (J = 7.19 Hz), C 1.78 (J = 7.13 Hz), D 1.167 (J = 7.70 Hz), E 1.35 ( J = 7.43 Hz), F 0.95 (J = 7.33 Hz) The spectrum and ChemNMR 1H Estimate (ChemDraw), the structural formula was determined as the following 3-nitrohexane (3-nitrohexane). The structural formula is shown below, and FIG. 19 shows the NMR data.

  From these analysis results, each peak of GC in the reaction solution at 300 ° C./40 MPa was assigned as shown in FIG.

(3) Case of Nitrobenzene Solvent FIG. 21 shows the GC analysis result of the reaction solution at 275 ° C./40 MPa. The two main peaks associated with the nitro compound are 9.16 and 9.39. 5.18 and 6.16 are nitrobenzene used as a solvent and naphthalene as a raw material.

  Retention times of 9.16 and 9.36 were determined by the same method as in hexane, and 9.16 and 9.36 were 1-nitronaphthalene and 2-nitronaphthalene, respectively. It was. Each attribution is shown in FIG.

  As described above in detail, the present invention relates to a method for selecting a nitration solvent for a solid organic compound and a nitration reaction method for a substrate organic compound. In the nitration reaction method, the yield and selectivity of the target nitro compound can be significantly improved. In addition, according to the present invention, a nitration reaction method capable of improving the yield and selectivity of a nitro compound obtained in a reaction field of high-temperature and high-pressure water can be provided. In addition, according to the present invention, a production system using a new nitration reaction method using high-temperature and high-pressure water can be constructed and provided. In the present invention, when selecting a solid solvent to be nitrated, it is possible to select a nitration solvent capable of finding a suitable solvent by previously comparing the nitration temperature zone of the substrate and the nitration temperature zone of the solvent. It is useful as a method and to provide a new nitration reaction method.

The conceptual diagram of the nitration reaction system by high temperature / high pressure water is shown. 1 shows hexane in a nitration reaction system in high temperature and high pressure (40 MPa) water. The gas chromatography of the reaction liquid which nitrated naphthalene with the hexane solvent is shown. The nitration temperature range of the substrate and the solvent is shown. The micro tube continuous reaction apparatus for nitric acid resistant environment is shown. 1 shows hexane in a nitration reaction system in high temperature and high pressure (40 MPa) water. The nitration temperature range plotted with the total yield of nitrated hexane is shown. The gas chromatography of the reaction liquid which nitrated naphthalene with the hexane solvent is shown. The yield curve and temperature of the total nitro compound of hexane and naphthalene are shown. The nitrobenzene nitration reaction temperature zone is shown. This shows the nitration of naphthalene using nitrobenzene as a solvent. 2 shows GC of a reaction solution of naphthalene nitrated in a hexane solvent and a 300 ° C./40 MPa reaction solution. The comparison of the MS spectrum of 1-nitronaphthalene is shown. The comparison of the infrared spectrum of 1-nitronaphthalene is shown. A comparison of mass spectra of 2-nitronaphthalene is shown. The comparison of the infrared spectrum of 2-nitronaphthalene is shown. The comparison of the infrared spectrum of 1-nitronaphthalene is shown. The comparison of the NMR spectrum of 2-nitronaphthalene is shown. The comparison of the NMR spectrum of 2-nitronaphthalene is shown. The attribution (300 degreeC / 40 Mpa) of the naphthalene nitration product of a hexane solvent is shown. Fig. 2 shows GC of nitrobenzene, solvent naphthalene nitration, and 275 ° C / 40 MPa reaction solution. The GC of a 275 ° C./40 MPa reaction solution is shown.

Claims (7)

  Substrate for use in a nitration reaction method in which nitration of a substrate organic compound is performed using a microtube continuous reaction apparatus for nitric acid resistant environment using nitric acid as a nitrogen source in a reaction field of high-temperature high-pressure water. A method for selecting a nitration solvent for an organic compound, comprising comparing a nitration temperature region of a substrate with a nitration temperature region of a solvent, and selecting a solvent by utilizing a difference between the temperature regions of the two. To select a nitrating solvent for the substrate organic compound.   The method for selecting a nitration solvent according to claim 1, wherein the reaction field of the high-temperature high-pressure water is a micro-reaction field having a small reaction volume.   The method for selecting a nitration solvent according to claim 1, wherein the nitration reaction of the substrate organic compound is carried out using a continuous microtube for nitric acid-resistant environment in the presence of dilute nitric acid.   The method for selecting a nitration solvent according to claim 1, wherein the temperature and pressure conditions of the high-temperature high-pressure water are 200 to 400 ° C and 25 to 40 MPa, respectively.   As a microtube continuous reactor for nitric acid resistant environment, a microtube reactor installed in an oven that can be maintained at a set temperature, a supply device that supplies high-temperature and high-pressure water to the nitrogen source reagent and the substrate, and at least carrier water By having a structure in which a continuous reaction system is constructed by connecting a high-pressure pump for feeding liquid, introducing a nitrogen source reagent and a substrate, and a cooling device for cooling a reaction product by a piping system so that the reaction product can be continuously reacted. The method for selecting a nitration solvent according to claim 1, wherein the nitration reaction of the substrate organic compound is carried out using the microtube continuous reaction apparatus for nitric acid resistant environment characterized.   6. A nitration reaction method in which nitration of a substrate organic compound is carried out using a microtube continuous reaction apparatus for nitric acid resistant environment using nitric acid as a nitrogen source in a reaction field of high temperature and high pressure water. A nitration reaction method of a substrate organic compound, wherein the nitration reaction of the substrate organic compound is performed using the nitration solvent selected by the method according to any one of the above.   The method for nitration of a substrate organic compound according to claim 6, wherein the yield and selectivity of the target nitro compound are improved by the nitration reaction method.