GC (Gas Chromatography) detection method of p-chlorophenylacetonitrile

Abstract

The GC detection method comprises the following steps: dissolving p-chlorobenzyl alcohol and 2-chlorobenzyl cyanide with methanol to obtain an impurity stock solution; 4-chlorophenylacetonitrile is added into the impurity stock solution, methanol is used for ultrasonic dissolution and volume metering to serve as a system applicability solution, the system applicability solution is injected into a gas chromatograph, separation of 4-chlorophenylacetonitrile and impurities of 4-chlorophenylacetonitrile is completed, and the content and purity of related substances are detected; according to the method, a TG-WAXMS chromatographic column, an FID hydrogen flame detector and a gradient heating program are adopted for separation, p-chlorophenylacetonitrile and impurities thereof can be rapidly separated, and the method is high in specificity, sensitivity and accuracy and suitable for detecting the content and purity of related substances of p-chlorophenylacetonitrile as a medical intermediate.

Description

Technical Field

[0001] The invention belongs to the technical field of p-chlorobenzeneacetonitrile detection, and specifically relates to a GC detection method for p-chlorobenzeneacetonitrile. Background Art

[0002] 4-Chlorobenzyl cyanide is an important fine chemical with a wide range of uses, including organic synthesis and pharmaceutical intermediates. As a pharmaceutical intermediate, it can be used to synthesize chlorpheniramine maleate, pyrimethamine, etc. Its molecular formula is C8H6ClN and its structural formula is:

[0003]

[0004] As a pharmaceutical intermediate, reasonable control of this compound can minimize the possible introduction of impurities, and quality control of the related substances and purity of 4-chlorophenylacetonitrile is required. So far, there are few detection methods for this compound. Summary of the invention

[0005] The object of the present invention is to provide a GC detection method for rapidly separating p-chlorobenzeneacetonitrile and its impurities, which is used for determining the content and purity of related substances of p-chlorobenzeneacetonitrile.

[0006] In order to solve the above technical problems, a technical solution adopted by the present invention is: a GC detection method for p-chlorobenzeneacetonitrile, using gas chromatography, SHIMADZU GC-2010Pro equipped with FID hydrogen flame ionization detector, GC detection conditions are as follows: chromatographic column: TG-WAXMS 0.32mm×30m, 0.25μm; injection port temperature: 200℃; detector temperature: 250℃; mobile phase: hydrogen flow rate 30mL / min; air flow rate 400mL / min; nitrogen tail blowing flow rate 40mL / min; column flow rate 1.0mL / min;

[0007] Temperature gradient program: initial column temperature was 60 °C, increased to 250 °C at a rate of 8 °C / min, and maintained for 2 min;

[0008] The following steps are involved:

[0009] (1) Take 10 mg of p-chlorobenzyl alcohol and 2-chlorobenzyl acetonitrile respectively, dissolve them in 10 mL of methanol as impurity stock solution; then take 1.0 mL of p-chlorobenzyl alcohol stock solution and 2-chlorobenzyl acetonitrile stock solution respectively in the same 100 mL volumetric flask, add methanol to dissolve by ultrasonication, and then dilute to the mark as the addition stock solution;

[0010] (2) Take 10 mg of p-chlorophenylacetonitrile in a 10 mL volumetric flask, add 1.0 mL of the additive stock solution, add methanol to dissolve by ultrasonication, and then dilute to the mark as the system suitability solution;

[0011] (3) Take 1 μL of the system suitability solution and inject it into the gas chromatograph to separate 4-chlorophenylacetonitrile and its impurities, record the chromatogram, and detect the content and purity of related substances.

[0012] Furthermore, the concentration of p-chlorobenzeneacetonitrile in the system suitability solution in step (2) is 1 mg / mL.

[0013] Furthermore, in the step (3), the injection port adopts a split mode with a split ratio of 10:1.

[0014] Furthermore, the chromatographic column is a highly polar capillary mass spectrometry column.

[0015] Furthermore, the detector is a SHIMADAZU gas chromatograph with a FID detector.

[0016] Furthermore, in the step (3), the purity of p-chlorophenylacetonitrile is obtained by area normalization method, and the content of related substances is obtained by external standard method.

[0017] The beneficial effects of the present invention are:

[0018] 1) The present invention adopts a TG-WAXMS 0.32mm×30m, 0.25μm strong polar capillary mass spectrometer column, which can effectively separate impurities. The minimum separation between the known impurities and the main peak is 10, the specificity is good, the whole running time of the method is within 25.75min, and the related substances and contents are analyzed by the same method without any parameter adjustment, and the method has the ability to quickly complete the analysis and detection. At the same time, the method can be directly converted to a gas chromatography-mass spectrometry detector for the study of impurities;

[0019] 2) This method uses gas chromatography, which is simpler to operate and has lower analysis costs than liquid phase analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a typical blank solution spectrum of the related substance detection method for p-chlorophenylacetonitrile;

[0021] Figure 2 This is a typical specific solution spectrum of the detection method for related substances of p-chlorophenylacetonitrile;

[0022] Figure 3 This is a typical sample solution spectrum for the detection method of related substances of p-chlorophenylacetonitrile. DETAILED DESCRIPTION

[0023] In order to clearly illustrate the technical features of the present solution, the present application is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0024] Embodiment 1:

[0025] 1. Exclusivity

[0026] Solution preparation:

[0027] Blank solution: methanol

[0028] p-Chlorophenylacetonitrile reference solution: Accurately weigh 10.06 mg of p-chlorophenylacetonitrile reference substance into a 10 ml volumetric flask, add methanol to dissolve by ultrasonication, and then dilute to the mark.

[0029] p-Chlorobenzyl alcohol stock solution: Accurately weigh 10.04 mg of p-chlorobenzyl alcohol reference substance into a 10 ml volumetric flask, add methanol to dissolve by ultrasonication, and then dilute to the mark.

[0030] 2-Chlorobenzeneacetonitrile stock solution: Accurately weigh 10.13 mg of 2-chlorobenzeneacetonitrile reference substance into a 10 ml volumetric flask, add methanol to dissolve by ultrasonication, and then dilute to the mark.

[0031] Add stock solution: Take 1.0 mL of p-chlorobenzyl alcohol stock solution and 1.0 mL of 2-chlorobenzeneacetonitrile stock solution respectively in the same 100 mL volumetric flask, add methanol to dissolve by ultrasonication and then dilute to the mark.

[0032] Test sample solution: Accurately weigh 104.98 mg of the test sample into a 100 ml volumetric flask, add methanol and ultrasonically dissolve it, then dilute to the mark.

[0033] Mixed solution: Accurately weigh 10.50 mg of p-chlorophenylacetonitrile into a 10 ml volumetric flask, add 1 ml of the reserve solution, add methanol to dissolve by ultrasonication, and then dilute to the mark.

[0034] Gas chromatography detection conditions: Chromatographic instrument: SHIMADZU GC-2010Pro with FID hydrogen flame ionization detector; Chromatographic column: TG-WAXMS 0.32mm×30m, 0.25μm; Inlet temperature: 200℃; Detector temperature: 250℃; Mobile phase: Hydrogen flow rate 30mL / min; Air flow rate 400mL / min; Nitrogen tail flow rate 40mL / min; Column flow rate 1.0mL / min;

[0035] Temperature gradient program: initial column temperature was 60 °C, increased to 250 °C at a rate of 8 °C / min, and maintained for 2 min;

[0036] Take 1 μL of blank solution, p-chlorobenzyl acetonitrile control solution, p-chlorobenzyl alcohol stock solution, 2-chlorobenzyl acetonitrile stock solution, test solution, and mixed solution, inject into gas chromatograph, and record chromatogram. The results are shown in Table 1. The separation degree between p-chlorobenzyl acetonitrile peak and impurity peak meets the requirements, indicating that the method has good specificity. The chromatogram is shown in the attached figure. Figures 1 to 3 It can be seen that each peak has a good shape and can be completely separated with good separation.

[0037] Table 1 Specificity results

[0038]

[0039] Example 2

[0040] 2. Limit of detection and limit of quantification

[0041] p-Chlorophenylacetonitrile stock solution: Accurately weigh 159.69 mg of p-Chlorophenylacetonitrile reference substance into a 100 ml volumetric flask, add methanol and ultrasonically dissolve it, then dilute to the mark.

[0042] Quantitation limit solution: Accurately pipette 20.0 ml of the stock solution and 1.0 ml of the p-chlorophenylacetonitrile stock solution into the same 100 ml volumetric flask, dilute to the mark with methanol, and mix well to obtain the quantitation limit stock solution. Accurately pipette 1.5 ml into a 10 ml volumetric flask, dilute to the mark with methanol, and mix well to obtain the quantitation limit solution.

[0043] Detection limit solution: Accurately pipette 3.0 ml of the above quantification limit solution into a 10 ml volumetric flask, ultrasonically dissolve it with methanol and dilute it to the scale.

[0044] Accurately take 1 μL of each solution, inject it into the gas chromatograph, and record the chromatogram. The results are shown in Tables 2 to 7.

[0045] Table 2 Detection results of the quantitative limit of p-chlorobenzyl alcohol

[0046]

[0047] Table 3 Detection limit results of p-chlorobenzyl alcohol

[0048]

[0049] Table 4 Quantitative limit detection results of 2-chlorobenzeneacetonitrile

[0050]

[0051] Table 5 Detection limit results of 2-chlorobenzeneacetonitrile

[0052]

[0053] Table 6 Detection results of quantification limit of p-chlorobenzeneacetonitrile

[0054]

[0055] Table 7 Detection limit results of p-chlorobenzeneacetonitrile

[0056]

[0057] Example 3

[0058] 3. Linear range

[0059] Blank solution: methanol

[0060] p-Chlorophenylacetonitrile stock solution: Same as p-Chlorophenylacetonitrile stock solution under “Limit of Quantitation and Limit of Detection”.

[0061] Linear solution ①: Accurately pipette 20.0 ml of the stock solution added under the "Specificity" item and 20.0 ml of the p-chlorophenylacetonitrile stock solution into the same 100 ml volumetric flask, ultrasonically dissolve and dilute to the scale with methanol, and mix well.

[0062] Linear solution ②: Accurately pipette 7.5 mL of linear solution ① into a 10 mL volumetric flask and add methanol to dilute to the mark.

[0063] Linear solution ③: Accurately pipette 5.0 mL of linear solution ① into a 10 mL volumetric flask and add methanol to dilute to the mark.

[0064] Linear solution ④: Accurately pipette 4.0 mL of linear solution ① into a 10 mL volumetric flask and add methanol to dilute to the mark.

[0065] Linear solution⑤: that is, the quantitative limit solution under the item of “quantitation limit and detection limit”.

[0066] Accurately pipette 1 μL of linear solution ① to ⑤ respectively, inject into gas chromatograph, record chromatogram, plot peak area against concentration, calculate regression equation and correlation coefficient by least square method, the results are shown in Tables 8 to 10.

[0067] Linear curves such as Figures 1 to 3 , linear curve correlation coefficient R of p-chlorobenzyl alcohol 2 =0.9923, linear equation y = 415.42x + 48.328, good linear relationship in the concentration range of 0.3012 ~ 2.0008μg / mL; 2-chlorobenzene acetonitrile linear curve correlation coefficient R 2 =0.9956, linear equation y=515.15x+48.328, good linear relationship in the concentration range of 0.3039-2.026μg / ml; unknown impurity (p-chlorophenylacetonitrile) linear curve correlation coefficient R2=0.9955, linear equation y=523.81x-32.082, good linear relationship in the concentration range of 0.3149-2.099μg / mL;

[0068] Table 8 Linearity results of p-chlorobenzyl alcohol

[0069]

[0070] Table 9 2-Chlorophenylacetonitrile linear results

[0071]

[0072] Table 10 Linear results of unknown impurity (p-chlorophenylacetonitrile)

[0073]

[0074] Example 4

[0075] 4. Accuracy

[0076] Blank solution: methanol

[0077] Sample blank solution: Weigh 10.15 mg of the test sample into a 10 mL volumetric flask, dissolve and dilute to the mark with methanol by ultrasonication, and mix well.

[0078] Accuracy test solution ①: Weigh 10.44 mg of the test sample into a 10 mL volumetric flask, add 0.5 mL of the stock solution under the "Specificity" item, dissolve and dilute to the scale with methanol ultrasonically, and mix well.

[0079] Accuracy test solution ②: Weigh 10.04 mg of the test sample into a 10 mL volumetric flask, add 1.0 mL of the stock solution under the "Specificity" item, dissolve and dilute to the scale with methanol by ultrasonication, and mix well.

[0080] Accuracy test solution ③: Weigh 10.40 mg of the test sample into a 10 mL volumetric flask, add 1.5 mL of the stock solution under the "Specificity" item, dissolve and dilute to the scale with methanol by ultrasonication, and mix well.

[0081] Accurately pipette 1 μL of accuracy test solution ①~③ respectively, inject into gas chromatograph, record chromatogram, the results are shown in Tables 11~12, known impurity accuracy experiment, concentration 50~150%, recovery rate and RSD both meet the recognition standard, known impurity accuracy is good.

[0082] Table 11 Accuracy test results of p-chlorobenzyl alcohol

[0083]

[0084] Table 12 2-Chlorophenylacetonitrile accuracy test results

[0085]

[0086] Example 5

[0087] 5. Sample addition precision

[0088] Blank solution: methanol

[0089] Sample blank solution: Weigh 10.15 mg of the test sample into a 10 mL volumetric flask, dissolve and dilute to the mark with methanol by ultrasonication, and mix well.

[0090] Addition precision solution: Accurately weigh 10.01 mg, 10.23 mg, 10.15 mg, 10.27 mg, 10.14 mg, and 10.11 mg of p-chlorophenylacetonitrile samples into 6 10 ml volumetric flasks, add 1.0 ml of the stock solution under the "specificity" item to each, dissolve and dilute to the scale with methanol ultrasonically, and mix well.

[0091] Take 1 μL of blank solution, sample blank solution, and 6 portions of sample precision solution, inject them into the gas chromatograph, and record the chromatogram. The results are shown in Table 13. In the sample precision experiment, all known recoveries and RSDs meet the acceptance criteria, and the sample precision results are good.

[0092] Table 13 Sample addition precision results

[0093]

[0094] The above embodiments are only illustrative of the principles and effects of the present invention, as well as some embodiments of its application. For those skilled in the art, several modifications and improvements may be made without departing from the creative concept of the present invention, and all of these belong to the protection scope of the present invention.

Claims

1. A GC detection method for p-chlorobenzeneacetonitrile, characterized in that: Gas chromatography, SHIMADZU GC-2010Pro equipped with FID hydrogen flame ionization detector, GC detection conditions are as follows: Chromatographic column: TG-WAXMS 0.32mm×30m, 0.25μm; Inlet temperature: 200°C; Detector temperature: 250°C; Mobile phase: hydrogen flow rate 30mL / min; air flow rate 400mL / min; nitrogen tail gas flow rate 40mL / min; column flow rate 1.0mL / min; Temperature gradient program: initial column temperature was 60 °C, increased to 250 °C at a rate of 8 °C / min, and maintained for 2 min; The specific steps include: (1) Take p-chlorobenzyl alcohol and 2-chlorophenylacetonitrile, add appropriate amount of methanol to dissolve them respectively to make the concentration of 1 mg / mL as impurity stock solution; (2) respectively mixing the p-chlorobenzyl alcohol stock solution and the 2-chlorobenzeneacetonitrile stock solution obtained in step 1), adding methanol to dilute the mixture 100 times and using the mixture as the added stock solution; (3) Take an appropriate amount of p-chlorophenylacetonitrile, add an appropriate amount of additive stock solution, add methanol and ultrasonically dissolve it so that the concentration of p-chlorophenylacetonitrile is 1 mg / mL and the concentration of each impurity is 5 μg / mL, which is used as the system suitability solution; (4) Take 1 μL of the system suitability solution and inject it into the gas chromatograph to separate p-chlorophenylacetonitrile and its impurities, record the chromatogram, and detect the content and purity of related substances.

2. A GC detection method for p-chlorobenzeneacetonitrile according to claim 1, characterized in that, In the step (4), the injection port adopts a split mode with a split ratio of 10:

1.

3. A GC detection method for p-chlorobenzeneacetonitrile according to claim 1, characterized in that, The chromatographic column is a highly polar capillary mass spectrometry column.

4. A GC detection method for p-chlorobenzeneacetonitrile according to any one of claims 1 to 3, characterized in that, In the step (4), the purity of p-chlorophenylacetonitrile is obtained by area normalization method, and the content of related substances is obtained by external standard method.

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