Apparatus and method for the condensed phase production of trisilylamine

Patent metadata

Field	Value
Publication number	US-9446958-B2
Application number	US-201314065088-A
Country	US
Kind code	B2
Filing date	Oct 28, 2013
Priority date	Oct 7, 2011
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

The present invention is directed to a condensed phase batch process for synthesis of trisilylamine (TSA). An improved synthesis process that incorporates a solvent to help promote a condensed-phase reaction between ammonia gas (or liquid) and liquified monochlorosilane (MCS) in good yields is described. This process facilitates the removal of the byproduct waste with little to no reactor down time, substantial reduction of down-stream solids contamination and high-purity product from first-pass distillation.

First claim

We claim:

1. A process for preparing trisilylamine comprising:
(a) adding a solvent to a reactor vessel;
(b) adding monohalosilane into the solvent to form a solution;
(c) adding anhydrous ammonia into the solution to form a reaction mixture;
(d) forming trisilylamine in the reaction mixture;
(e) separating trisilylamine from the reaction mixture; and
(f) purifying trisilylamine;
wherein the solvent has a donor number (DN) between about 6 to about 28 and a solvent polarity (E T N ) from about 0.1 to about 0.4.

2. The process of claim 1 wherein the solvent is selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons, symmetric ethers, unsymmetric ethers, poly-ethers, crown ethers, chloro-fluorocarbons and mixtures thereof.

3. The process of claim 1 further comprising adjusting the solvent temperature prior to adding the monohalosilane into the solvent to form a solution.

4. The process of claim 1 wherein the reactor vessel is maintained at a pressure of about two atmospheres or less.

5. The process of claim 1 wherein the monohalosilane is selected from the group consisting of monofluorosilane, monochlorosilane, monobromosilane and monoiodosilane.

6. The process of claim 1 wherein the monohalosilane is monochlorosilane.

7. The process of claim 3 wherein the solvent temperature is adjusted to be between about 70° C. to about −78° C.

8. The process of claim 3 wherein the solvent temperature is adjusted to be between about 50° C. to about −20° C.

9. The process of claim 1 wherein the molar ratio of monohalosilane to anhydrous ammonia is from about 1.05:1 to about 3:1.

10. A process for preparing silylamines comprising:
(a) adding a solvent to a reactor vessel;
(b) adding monohalosilane into the solvent to form a solution;
(c) adding anhydrous ammonia into the solution to form a reaction mixture;
(d) forming silylamines in the reaction mixture;
(e) separating silylamines from the reaction mixture; and
(f) purifying silylamines;
wherein the solvent has a donor number (DN) between about 6 to about 28 and a solvent polarity (E T N ) from about 0.1 to about 0.4.

11. The process of claim 10 wherein the solvent is selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons, symmetric ethers, unsymmetric ethers, poly-ethers, crown ethers, chloro-fluorocarbons and mixtures thereof.

12. The process of claim 10 further comprising adjusting the solvent temperature prior to adding the monohalosilane into the solvent to form a solution.

13. The process of claim 10 wherein the reactor vessel is maintained at a pressure of about two atmospheres or less.

14. The process of claim 10 wherein the monohalosilane is selected from the group consisting of monofluorosilane, monochlorosilane, monobromosilane and monoiodosilane.

15. The process of claim 10 wherein the monohalosilane is monochlorosilane.

16. The process of claim 12 wherein the solvent temperature is adjusted to be between about 70° C. to about −78° C.

17. The process of claim 12 wherein the solvent temperature is adjusted to be between about 50° C. to about −20° C.

18. The process of claim 10 wherein the molar ratio of monohalosilane to anhydrous ammonia is from about 1.05:1 to about 3:1.

19. A process for preparing trisilylamine comprising:
(a) adding a solvent to a reactor vessel;
(b) adding monohalosilane into the solvent to form a solution;
(c) adding anhydrous ammonia into the solution to form a reaction mixture;
(d) forming trisilylamine in the reaction mixture;
(e) separating trisilylamine from the reaction mixture; and
(f) purifying the trisilylamine;
wherein the solvent is selected from the group consisting of acetonitrile, butanenitrile, diethyl ether, di-n-propyl ether, di-isopropyl ether, dibenzyl ether, ethyl phenyl ether, bis(2-chloroethyl)ether, diglyme, furan, tetrohydrofuran (THF), 2-methyl THF, tetrahydropyrane, N,N-dimethylaniline and 1,4-dioxane.

20. The process of claim 19 further comprising adjusting the solvent temperature prior to adding the monohalosilane into the solvent to form a solution.

21. The process of claim 20 wherein the solvent temperature is adjusted to be between about 50° C. to about −20° C.

22. The process of claim 19 wherein the molar ratio of monohalosilane to anhydrous ammonia is from about 1.05:1 to about 3:1.

23. The process of claim 19 wherein the solvent is N,N-dimethylaniline.

Assignees

• L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude
• L'Air Liquide Soc Anonyme L'Etude Et L'Exploitation Des Procedes Georges Claude

Inventors

• Ritter Iii Cole J
• Stephens Matthew Damien

Classifications

• C01B21/087 Primary

  containing one or more hydrogen atoms · CPC title

• C01B33/04 Primary

  Hydrides of silicon · CPC title