Central control method for production of tetra (dimethylamino) tin
By monitoring the tetra(dimethylamino)tin production process using a central control detection method, the safety hazards and low yield problems caused by unreacted active substances were solved, achieving safe and high-yield production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YUANZHAN MATERIAL TECHNOLOGY (TAIZHOU) CO LTD
- Filing Date
- 2026-01-15
- Publication Date
- 2026-05-01
AI Technical Summary
In the production process of tetra(dimethylamino)tin, the incomplete reaction of active substances leads to safety hazards and low raw material utilization in subsequent processing.
The reaction process is monitored and complete by using central control detection methods, including quenching observation of water mist, phenolphthalein indicator titration, and nuclear magnetic resonance testing.
It improved production safety, increased raw material utilization and product yield, and achieved operability and stability in production.
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Figure CN121949385A_ABST
Abstract
Description
A method for controlling the production of tetra(dimethylamino)tin Technical Field
[0001] This invention relates to the field of organic synthesis technology, specifically to a method for controlling the production of tetra(dimethylamino)tin. Background Technology
[0002] In ALD (Atomic Layer Deposition) technology, tetra(dimethylamino)tin, due to its high vapor pressure and chemical reactivity, enables the atomically precise deposition of SnO2 thin films. By alternately introducing precursors and oxidants (such as H2O or O3), uniform, dense, and thickness-controllable films (typically ranging from 1 to 100 nm) can be formed on silicon, glass, or flexible substrates. This technological advantage makes it particularly important in micro- and nano-electronic devices, for example, in the fabrication of highly sensitive gas sensors. By controlling the film pore size and surface active sites, the response speed and selectivity to target gases can be significantly improved.
[0003] In CVD (chemical vapor deposition) applications, tetrakis(dimethylamino)tin is commonly used for the rapid deposition of large-area thin films. High-quality SnO2 thin films can be generated at low temperatures (200-400℃) through thermal decomposition or plasma-assisted reactions, making them suitable for transparent conductive layers in solar cells or as an ITO replacement material for touchscreens. Their advantage lies in enabling mass production while maintaining stable photoelectric properties of the film. For example, in perovskite solar cells, the SnO2 electron transport layer, prepared via CVD, can effectively reduce interface defects and improve device efficiency to over 22%.
[0004] The core value of tetratetra(dimethylamino)tin in ALD / CVD lies in its reliability as a high-purity precursor. By optimizing deposition parameters (such as temperature, pressure, and pulse time), the crystal structure, surface roughness, and electrical properties of the thin film can be precisely controlled, meeting the stringent requirements of advanced semiconductor devices for material uniformity and functionalization. In the future, with the advancement of nanofabrication technology, its application potential in flexible electronics, wearable devices, and 3D integrated devices will be further unleashed, driving the innovation of next-generation optoelectronic devices.
[0005] The raw materials for producing tetra(dimethylamino)tin include dimethylamine, n-butyllithium, and tin tetrachloride. During large-scale production, highly reactive raw materials and intermediate products are used, such as n-butyllithium and dimethylaminolithium, which are highly flammable upon contact with air. Product formation requires slow processing at room temperature or under heating conditions. Factors such as the amount of feed, feeding rate, concentration, stirring speed, and temperature all affect the reaction process. If these active substances are not completely consumed during the synthesis stage and end up in the reactor residue or filter residue, this will place a significant safety burden on the subsequent processing.
[0006] Therefore, an intermediate control step is needed in the production process of tetra(dimethylamino)tin to determine whether these active substances have been fully converted into the product, in order to improve the safety of production. Summary of the Invention
[0007] This invention addresses the shortcomings of existing technologies by providing a method for controlling the production of tetra(dimethylamino)tin. This method monitors the reaction progress of each step in the tetra(dimethylamino)tin production process, ensuring complete reaction at each step and preventing the accumulation of unreacted substances in residues or reactor waste during subsequent separation processes, which could lead to safety hazards. Through this central control monitoring, the method significantly improves raw material utilization and increases product yield. It also enhances the operability, stability, and repeatability of the production process, providing a more intuitive understanding and control of the experimental progress.
[0008] To address the aforementioned technical problems, this invention provides a method for controlling the production of tetra(dimethylamino)tin, the method comprising:
[0009] S1, n-butyllithium and dimethylamine react in a solvent to produce dimethylaminolithium;
[0010] S2, Adding tin tetrachloride reacts to produce tetra(dimethylamino)tin;
[0011] The control detection method for step S1 is as follows: Take V1 volume of reaction solution S1, dry it, add water to quench it, and hydrolyze the unreacted n-butyllithium to generate lithium hydroxide; if water mist appears during the quenching process, the reaction is directly determined to be incomplete; if no water mist is found during the quenching process, add phenolphthalein indicator, titrate with standard hydrochloric acid solution and calculate the reaction progress. When the reaction progress is ≥98%, the reaction is determined to be complete and proceed to step S2; otherwise, the reaction is determined to be incomplete.
[0012] The control detection method for step S2 is as follows: Take the S2 reaction solution, dry it, and then perform NMR testing. When the area integral ratio of the characteristic peak A of the product tetra(dimethylamino)tin to the characteristic peak B of the intermediate product tri(dimethylamino)tin chloride in the NMR spectrum is >100:3.3, the reaction is judged to be completely stopped; otherwise, the reaction is judged to be incomplete.
[0013] According to experimental test data, dimethylamine and n-butyllithium can basically react completely in about 5-6 hours at the reaction temperature in step S1. However, the reaction progress is related to factors such as reaction temperature, concentration, stirring speed, solid amount, feed amount, feeding speed, and operator. Therefore, the actual process is not entirely consistent, and it is necessary to judge whether the reaction is complete based on the reaction situation. The mid-control detection method in step S1 first qualitatively determines whether the reaction is complete by observing the presence of water mist during quenching, which is convenient and quick. Subsequently, the reaction progress can be quantitatively calculated by adding phenolphthalein indicator and titrating with hydrochloric acid. Specifically, when water mist appears during quenching, the phenolphthalein indicator turns red, requiring more hydrochloric acid during titration; when there is no obvious water mist during quenching, the phenolphthalein indicator turns colorless or light pink, requiring less hydrochloric acid during titration. The mid-control detection method for step S1 of this invention is simple and quick.
[0014] According to experimental data, lithium dimethylamino and tin tetrachloride react completely in approximately 12-14 hours at the S2 step reaction temperature. However, the reaction progress is affected by factors such as reaction temperature, concentration, stirring speed, solid quantity, feed rate, feeding speed, and operator skill. Therefore, the actual process is not entirely consistent, and it is necessary to determine whether the reaction is complete based on the reaction conditions. The mid-level control detection of the S2 step is determined by the area integral ratio of each characteristic peak in the NMR spectrum, which is simple to operate.
[0015] Furthermore, the method for titrating and calculating the reaction progress using standard hydrochloric acid solution is as follows:
[0016] The molar concentration of unreacted n-butyllithium in the S1 reaction solution of volume V1 is C1 = C2 × V2 ÷ V1; where C2 is the molar concentration of the standard hydrochloric acid solution and V2 is the volume of the standard hydrochloric acid solution consumed.
[0017] Reaction progress = 100% - (C1 / C0) × 100%, where C0 is the initial concentration (feed concentration) of n-butyllithium in the reaction solution of step S1.
[0018] Furthermore, in the control detection method of step S1, if it is determined that the reaction is not complete, the reaction time of step S1 is extended and / or the reaction temperature is increased to continue the reaction.
[0019] Furthermore, after the reaction continues in step S1, the control detection of step S1 is performed again until it is determined that the reaction has completely entered step S2.
[0020] Furthermore, the extension of the reaction time and / or increase of the reaction temperature in step S1 specifically means: extending the reaction time by 1-3 hours and increasing the reaction temperature by 5-10°C.
[0021] Furthermore, in the control detection method of step S2, if it is determined that the reaction is not complete, the reaction time of step S2 is extended and / or the reaction temperature is increased to continue the reaction.
[0022] Furthermore, after the reaction continues in step S2, the central control test of step S2 is performed again until the reaction is determined to be complete.
[0023] Furthermore, the extension of the reaction time and / or increase of the reaction temperature in step S2 specifically involves extending the reaction time by 1-6 hours and increasing the reaction temperature by 5-10°C.
[0024] Furthermore, when the characteristic peak C of polytetra(dimethylamino)tin appears in the NMR spectrum, and the area integral ratio of characteristic peak A to characteristic peak C is <100:3.3, the reaction is considered complete and the reaction is stopped. Further extending the reaction time will only increase product polymerization and reduce the yield.
[0025] Furthermore, the position of characteristic peak A is 2.81, the position of characteristic peak B is 2.86, and the position of characteristic peak C is 2.17-2.21.
[0026] The beneficial effects of this invention are:
[0027] This invention provides in-process monitoring of two reaction steps in the production of tetra(dimethylamino)tin, which can effectively monitor the content of active substances, determine the reaction progress, and ensure the completeness of each step. This greatly improves the safety of the production process and avoids the occurrence of a large amount of unreacted substances in the residue or reactor residue during subsequent separation processes, thus preventing safety hazards during the processing.
[0028] This invention, through central control detection, can greatly improve the utilization rate of raw materials and increase the yield of products; it also achieves operability, stability, and repeatability in production, and allows for a more intuitive understanding and control of the experimental process. Attached Figure Description
[0029] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0030] Figure 1 is the NMR spectrum of the tetra(dimethylamino)tin production process of the present invention after reacting with tin tetrachloride for 4 hours;
[0031] Figure 2 is the NMR spectrum of the tetra(dimethylamino)tin production process of the present invention after reacting with tin tetrachloride for 10 hours;
[0032] Figure 3 is the NMR spectrum of the tetra(dimethylamino)tin production process of the present invention after reacting with tin tetrachloride for 14 hours;
[0033] Figure 4 is the NMR spectrum of the tetra(dimethylamino)tin after 20 hours of reaction with tin tetrachloride during the production process of the present invention. Detailed Implementation
[0034] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0035] This embodiment relates to a method for controlling the production of tetra(dimethylamino)tin, the method comprising:
[0036] S1, n-butyllithium and dimethylamine react in a solvent to produce dimethylaminolithium;
[0037] S2, Adding tin tetrachloride reacts to produce tetra(dimethylamino)tin;
[0038] The control detection method for step S1 is as follows: Take V1 volume of reaction solution S1, dry it, add water to quench it, and hydrolyze the unreacted n-butyllithium to generate lithium hydroxide; if water mist appears during the quenching process, the reaction is directly determined to be incomplete; if no water mist is found during the quenching process, add phenolphthalein indicator, titrate with standard hydrochloric acid solution and calculate the reaction progress. When the reaction progress is ≥98%, the reaction is determined to be complete and proceed to step S2; otherwise, the reaction is determined to be incomplete.
[0039] The control detection method for step S2 is as follows: Take the S2 reaction solution, dry it, and then perform NMR testing. When the area integral ratio of the characteristic peak A of the product tetra(dimethylamino)tin to the characteristic peak B of the intermediate product tri(dimethylamino)tin chloride in the NMR spectrum is >100:3.3, the reaction is judged to be completely stopped; otherwise, the reaction is judged to be incomplete.
[0040] In this embodiment, the intermediate control detection in step S1 first qualitatively determines whether the reaction is complete by observing whether water mist is present during quenching, which is convenient and quick. Subsequently, the reaction progress can be calculated quantitatively by adding phenolphthalein indicator and titrating with hydrochloric acid. Specifically, when water mist appears during quenching, the added phenolphthalein indicator turns red, requiring more hydrochloric acid during titration; when there is no obvious water mist during quenching, the added phenolphthalein indicator turns colorless or light pink, requiring less hydrochloric acid during titration. The intermediate control detection in step S2 is determined by the area integral ratio of each characteristic peak in the NMR spectrum. The intermediate control detection methods in steps S1 and S2 of this embodiment are simple, quick, easy to operate, and reliable, providing accurate guidance for safe production.
[0041] As a preferred embodiment, the method for titrating and calculating the reaction progress with standard hydrochloric acid solution is as follows:
[0042] The molar concentration of unreacted n-butyllithium in the S1 reaction solution of volume V1 is C1 = C2 × V2 ÷ V1; where C2 is the molar concentration of the standard hydrochloric acid solution and V2 is the volume of the standard hydrochloric acid solution consumed.
[0043] Reaction progress = 100% - (C1 / C0) × 100%, where C0 is the initial concentration (feed concentration) of n-butyllithium in the reaction solution of step S1.
[0044] In a preferred embodiment, in the control detection method of step S1, if it is determined that the reaction is not complete, the reaction time of step S1 is extended and / or the reaction temperature is increased to continue the reaction; after the reaction continues in step S1, the control detection of step S1 is performed again until it is determined that the reaction has completely entered step S2; the extension of the reaction time of step S1 and / or the increase of the reaction temperature specifically means: extending the reaction time by 1-3 hours and increasing the reaction temperature by 5-10°C.
[0045] In a preferred embodiment, in the control detection method of step S2, if it is determined that the reaction is not complete, the reaction time of step S2 is extended and / or the reaction temperature is increased to continue the reaction; after the reaction continues in step S2, the control detection of step S2 is performed again until it is determined that the reaction is complete; the extension of the reaction time of step S2 and / or the increase of the reaction temperature specifically means: extending the reaction time by 1-6 hours and increasing the reaction temperature by 5-10°C.
[0046] As a preferred embodiment, when the characteristic peak C of polytetra(dimethylamino)tin appears in the NMR spectrum, and the area integral ratio of characteristic peak A to characteristic peak C is <100:3.3, the reaction is determined to be complete and the reaction is stopped. Further extending the time will only increase product polymerization and reduce the yield. The position of characteristic peak A is 2.81, the position of characteristic peak B is 2.86, and the position of characteristic peak C is 2.17-2.21.
[0047] Example 1
[0048] (1) After 2 hours of reaction between dimethylamine and n-butyllithium, a sample was taken to monitor the reaction. 10 mL of the supernatant was taken, the solvent was removed, and 10 mL of water was added to quench the heat generated during the process, resulting in water mist on the inner wall of the bottle. Phenolphthalein was added, and the color turned bright red. A certain concentration of hydrochloric acid (0.05 M / L) was used for titration, and the volume consumed was 48 mL. The consumption of n-butyllithium was calculated to be 75.04%. According to the experimental results, it is clear that the reaction was not complete. The reaction time was extended to continue the reaction. When the total reaction time was 5 hours, a sample was taken and the above-mentioned central control detection steps were repeated. There was basically no temperature change during quenching, no water mist, and the color of phenolphthalein added was light red. The volume of hydrochloric acid consumed was 1.5 mL, and the consumption of n-butyllithium was calculated to be 99.22%. At this point, the n-butyllithium had basically reacted completely, and the next step of the reaction could be carried out. N-butyllithium has high reactivity and is spontaneously combustible in air. Therefore, this step was basically confirmed to be complete before proceeding to the next experiment.
[0049] (2) After adding tin tetrachloride, after reacting for 4 hours, the NMR spectrum of the sample is shown in Figure 1. Based on the characteristic peak A:B:C (100:20.6:0.45), it is determined that the active substance has not been fully consumed. To verify this, the crude product yield was calculated to be only 70% and the crude product purity was 90%, which corroborates the NMR spectrum results. At this time, the reaction is not complete. The residue in the reactor is placed in the air, and the temperature rises from 25°C to 35°C within 2 minutes, posing a significant risk of spontaneous combustion. Therefore, it is necessary to determine that the reaction is complete.
[0050] (3) After 10 hours of reaction, the NMR spectrum of the sample is shown in Figure 2. According to the peak A:B:C (100:4.84:0.94), it is determined that there is still a small amount of active substance remaining. At this time, the crude product yield is 83% and the crude product purity is 95%. When the residue in the reactor is placed in the air, the temperature rises from 25℃ to 30℃ within 2 minutes, and there is basically no risk of spontaneous combustion.
[0051] (4) After 14 hours of reaction, the NMR spectrum of the sample is shown in Figure 3. According to the peak A:B:C (100:3.1:1.6), the active substance has been fully consumed. At this time, the crude product yield is 86% and the crude product purity is 96%. When the residue in the reactor is placed in the air, the temperature rises from 25℃ to 26℃ within 2 minutes, and there is basically no risk of spontaneous combustion.
[0052] (5) After 20 hours of reaction, the NMR spectrum of the sample is shown in Figure 4. According to the characteristic peaks A:B:C (100:0.78:20.72), the active substance has been fully consumed, but the proportion of characteristic peak C is relatively large. At this time, the crude product yield is reduced to 73%, the crude product purity is 92%, and the residue in the reactor is placed in the air. Within 2 minutes, the temperature rises from 25℃ to 35℃, and there is basically no risk of spontaneous combustion.
[0053] In summary, this invention utilizes centralized monitoring of the reaction process at each step, and verifies the reliability of the centralized monitoring method through yield analysis. This centralized monitoring method effectively monitors the content of active substances, judges the reaction progress, and ensures complete reaction at each step, greatly improving the safety of the production process and preventing large amounts of unreacted substances from remaining in the residue or reactor waste during subsequent separation processes, thus avoiding safety hazards during processing. Through centralized monitoring, this invention significantly improves raw material utilization and increases product yield; it also achieves operability, stability, and repeatability in production, providing a more intuitive understanding and control of the experimental process.
[0054] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.
Claims
1. A method for controlling the production of tetra(dimethylamino)tin, characterized in that, The production method of tetra(dimethylamino)tin includes: S1, reacting n-butyllithium and dimethylamine in a solvent to generate dimethylaminolithium; S2, adding tin tetrachloride to react and generate tetra(dimethylamino)tin; wherein, the control detection method of step S1 is as follows: take V1 volume of the S1 reaction solution, dry it, add water to quench it, and hydrolyze the unreacted n-butyllithium to generate lithium hydroxide; if water mist appears during the quenching process, it is directly determined that the reaction is incomplete; if no water mist is found during the quenching process, phenolphthalein indicator is added. The reaction is titrated with standard hydrochloric acid solution and the reaction progress is calculated. When the reaction progress is ≥98%, the reaction is considered complete and proceeds to step S2. Otherwise, the reaction is considered incomplete. The control detection method for step S2 is as follows: take the S2 reaction solution, dry it, and perform NMR testing. When the area integral ratio of the characteristic peak A of the product tetra(dimethylamino)tin to the characteristic peak B of the intermediate product tri(dimethylamino)tin chloride in the NMR spectrum is >100:3.3, the reaction is considered complete and the reaction is stopped. Otherwise, the reaction is considered incomplete.
2. The method for controlling the production of tetrakis(dimethylamino)tin as described in claim 1, characterized in that, The method for titrating and calculating the reaction progress with standard hydrochloric acid solution is as follows: the molar concentration of unreacted n-butyllithium in the V1 volume of S1 reaction solution is C1 = C2 × V2 ÷ V1; Wherein, C2 is the molar concentration of the standard hydrochloric acid solution, and V2 is the volume of the standard hydrochloric acid solution consumed; reaction progress = 100% - (C1 / C0) × 100%, where C0 is the initial concentration of n-butyllithium in the reaction solution of step S1.
3. The method for controlling the production of tetrakis(dimethylamino)tin as described in claim 1, characterized in that, In the control detection method of step S1, if it is determined that the reaction is not complete, the reaction time of step S1 is extended and / or the reaction temperature is increased to continue the reaction.
4. The method for controlling the production of tetrakis(dimethylamino)tin as described in claim 3, characterized in that, After the reaction continues in step S1, the central control detection of step S1 is performed again until it is determined that the reaction has completely entered step S2.
5. The method for controlling the production of tetrakis(dimethylamino)tin as described in claim 3, characterized in that, Specifically, extending the reaction time of step S1 and / or increasing the reaction temperature involves extending the reaction time by 1-3 hours and increasing the reaction temperature by 5-10°C.
6. The method for controlling the production of tetra(dimethylamino)tin as described in claim 1, characterized in that, In the control detection method of step S2, if it is determined that the reaction is not complete, the reaction time of step S2 is extended and / or the reaction temperature is increased to continue the reaction.
7. The method for controlling the production of tetra(dimethylamino)tin as described in claim 6, characterized in that, After the reaction continues in step S2, the central control test of step S2 is performed again until the reaction is determined to be complete.
8. The method for controlling the production of tetra(dimethylamino)tin as described in claim 6, characterized in that, Specifically, extending the reaction time of step S2 and / or increasing the reaction temperature involves extending the reaction time by 1-6 hours and increasing the reaction temperature by 5-10°C.
9. The method for controlling the production of tetra(dimethylamino)tin as described in claim 1, characterized in that, When the characteristic peak C of polytetra(dimethylamino)tin appears in the NMR spectrum, and the area integral ratio of characteristic peak A to characteristic peak C is <100:3.3, the reaction is considered complete and the reaction is stopped.
10. The method for controlling the production of tetra(dimethylamino)tin as described in claim 9, characterized in that, The position of characteristic peak A is 2.81, the position of characteristic peak B is 2.86, and the position of characteristic peak C is 2.17-2.21.