Claims
- 1. A method for preparing a high purity sterically hindered diaryl chlorophosphate or diaryl chlorothiophosphate which comprises:
(A) gradually introducing, at a temperature below about 120° C. and over a period greater than one hour, the reagent phosphoryl chloride or thiophosphoryl chloride into a mixture of at least one sterically hindered hydroxyaromatic compound and an effective amount of at least one catalyst in the absence of an organic solvent, to form a reaction mixture; and (B) gradually increasing the temperature of said reaction mixture to a final level in the range of about 135-150° C. over a period of less than about 10 hours; and (C) analyzing the reaction mixture to determine completeness of reaction, and optionally introducing at least one of hydroxyaromatic compound, phosphoryl chloride or thiophosphoryl chloride at said final temperature level to achieve a final stoichiometric 2:1 molar ratio of hydroxyaromatic compound to phosphoryl chloride or thiophosphoryl chloride.
- 2. A method according to claim 1 wherein the diaryl chlorophosphate or diaryl chlorothiophosphate has the formula
- 3. A method according to claim 1 wherein the at least one catalyst is an alkaline earth metal halide.
- 4. A method according to claim 3 wherein the amount of alkaline earth metal halide is in the range of about 2-5 mole percent based on total hydroxyaromatic compound.
- 5. A method according to claim 3 wherein the alkaline earth metal halide is magnesium chloride.
- 6. A method according to claim 1 wherein the temperature in step A is in the range of about 80-120° C.
- 7. A method according to claim 1 wherein the time period in step B is in the range of about 7-8 hours.
- 8. A method according to claim 1 wherein the hydroxyaromatic compound comprises 2,6-xylenol.
- 9. A method according to claim 1 wherein the molar ratio of phosphorus oxychloride to hydroxyaromatic compound is about 0.5:1.
- 10. The method of claim 1 in which the diaryl chlorophosphate or diaryl chlorothiophosphate is used without isolation in a subsequent reaction.
- 11. The method of claim 1 in which the diaryl chlorophosphate or diaryl chlorothiophosphate is isolated before use in a subsequent reaction.
- 12. A method for preparing high purity di-(2,6-xylyl) chlorophosphate or chlorothiophosphate which comprises:
(A) gradually introducing, at a temperature below about 120° C. and over a period greater than one hour, the reagent phosphoryl chloride or thiophosphoryl chloride into a mixture of 2,6-xylenol and an effective amount of magnesium chloride catalyst in the absence of an organic solvent to form a reaction mixture; (B) gradually increasing the temperature of said reaction mixture to a final level in the range of about 135-150° C. over a period of about 7-8 hours; and (C) analyzing the reaction mixture to determine completeness of reaction, and optionally introducing at least one of 2,6-xylenol, phosphoryl chloride or thiophosphoryl chloride at said final temperature level to achieve a final stoichiometric 2:1 molar ratio of 2,6-xylenol to phosphoryl chloride or thiophosphoryl chloride.
- 13. The method of claim 12 in which the di-(2,6-xylyl) chlorophosphate is used without isolation in a subsequent reaction.
- 14. The method of claim 12 in which the di-(2,6-xylyl) chlorophosphate is isolated before use in a subsequent reaction.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of copending U.S. application Ser. No. 09/537,035, filed Mar. 28, 2000, which claims the benefit of U.S. Provisional Application No. 60/135,755, filed May 25, 1999, and which applications are incorporated herein by reference.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60135755 |
May 1999 |
US |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09537035 |
Mar 2000 |
US |
Child |
09934933 |
Aug 2001 |
US |