Synthesis of alkyl tribenzanoate

• US 10,640,446 B2
• Filed: 05/23/2017
• Issued: 05/05/2020
• Est. Priority Date: 05/25/2016
• Status: Active Grant

• Current Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Original Assignee: SABIC Global Technologies BV (Government of Saudi Arabia)
• Inventors: Nandy, Ritesh, Patrick, Vishal, Nesakumar, Edward Joseph
• Primary Examiner(s): Cutliff, Yate K
• Application Number:
  US16/302,446
• Publication Number:
  US 20190292126A1
• Time in Patent Office: 1,078 Days
• CPC Class Codes: C07C 63/331 with all carboxyl groups bound to non-condensed rings
• CPC Class Codes: C07C 67/08 by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
• CPC Class Codes: C07C 69/76 Esters of carboxylic acids having a carboxyl group bound to a carbon atom of a six-membered aromatic ring

Abstract

A method of making alkyl tribenzanoates includes combining a phenyl tricarboxylic acid or chemical equivalent thereof with greater than or equal to 3.5 molar equivalents of a C₄-C₁₈ alkyl alcohol, based on the amount of phenyl tricarboxylic acid or chemical equivalent thereof, in the presence of 0.05 to 0.20 mol % of a titanium tetra-alkoxide catalyst, based on the total moles of phenyl tricarboxylic acid or chemical equivalent, at a temperature greater than 210° C. to form a reaction mixture having an acid value less than or equal to 0.5 as determined according to ASTM D1045.

Claims

1. A method of making alkyl tribenzanoates comprising:

combining a phenyl tricarboxylic acid or chemical equivalent thereof with greater than or equal to 3.5 molar equivalents of a C₄-C₁₈ alkyl alcohol, based on the amount of phenyl tricarboxylic acid or chemical equivalent thereof, in the presence of 0.05 to 0.20 mol % of a titanium tetra-alkoxide catalyst, based on the total moles of phenyl tricarboxylic acid or chemical equivalent, at a temperature greater than 210°

C. to form a reaction mixture having an acid value less than or equal to 0.5 as determined according to ASTM D1045.

2. The method of claim 1 further comprising neutralizing the reaction mixture with an aqueous caustic solution, and purging the neutralized reaction mixture with carbon dioxide.

3. The method of claim 2, further comprising distilling residual C₄-C₁₈ alkanol from the reaction mixture either prior to purging, subsequent to purging or both.

4. The method of claim 3, further comprising filtering the distilled reaction mixture after purging through celite, contacting the filtered reaction mixture with charcoal;

and

filtering the charcoal containing mixture to produce a product having an acid value less than 0.1 and an APHA color value less than 30 as determined according to ASTM D1045.

5. The method of claim 1, wherein the phenyl tricarboxylic acid or chemical equivalent thereof comprises trimellitic anhydride.

6. The method of any of claim 1, wherein the C₄-C₁₈ alkyl alcohol comprises 2-ethylhexyl alcohol.

7. The method of claim 1, wherein the titanium tetra-alkoxide catalyst comprises titanium tetra-isopropoxide catalyst.

8. The method of claim 1, wherein the reaction mixture has an acid value less than or equal to 0.3.

9. The method of claim 1, wherein the C₄-C₁₈ alkyl alcohol is present in an amount of 3.5 to 4.5 molar equivalents, based on the amount of phenyl tricarboxylic acid or chemical equivalent thereof.

10. The method of claim 1, wherein the temperature is less than or equal to 250°

C.

11. A method of making alkyl tribenzanoates comprising:

combining a phenyl tricarboxylic acid or chemical equivalent thereof with greater than or equal to 3.5 molar equivalents of a C₄-C₁₈ alkyl alcohol in the presence of 0.05 to 0.20 mol % of a titanium tetra-isopropoxide catalyst, based on the total moles of phenyl tricarboxylic acid or chemical equivalent, at a temperature greater than 210°

C. to form a reaction mixture;

neutralizing the reaction mixture with an aqueous caustic solution and purging the neutralized reaction mixture with carbon dioxide;

distilling any residual C₄-C₁₈ alkanol from the purged reaction mixture;

filtering the distilled reaction mixture through celite; and

contacting the filtered reaction mixture with charcoal to form a product having an acid value less than 0.1 and an APHA color value less than or equal to 30 both determined according to ASTM D1045.

12. The method of claim 11, further comprising distilling C₄-C₁₈ alkanol from the reaction mixture prior to neutralizing.

13. The method of claim 11, wherein the phenyl tricarboxylic acid or chemical equivalent thereof comprises trimellitic anhydride.

14. The method of claim 11, wherein the C₄-C₁₈ alkyl alcohol comprises 2-ethylhexyl alcohol.

15. A method of making alkyl tribenzanoates comprising:

combining a trimellitic acid or a trimellitic anhydride or a combination thereof with greater than or equal to 3.5 molar equivalents of a 2-ethylhexyl alcohol, based on the total moles of trimellitic acid or trimellitic anhydride or combination thereof, in the presence of 0.05 to 0.20 mol % of a titanium tetra-isopropoxide catalyst at a temperature greater than 210°

C. to form a reaction mixture having an acid value less than or equal to 0.3.

16. The method of claim 15 further comprising neutralizing the reaction mixture with an aqueous caustic solution, and purging the neutralized reaction mixture with carbon dioxide.

17. The method of claim 16, further comprising distilling residual C₄-C₁₈ alkanol from the reaction mixture either prior to purging, subsequent to purging or both.

18. The method of claim 17, further comprising filtering the distilled reaction mixture after purging through celite, contacting the filtered reaction mixture with charcoal;

and

filtering the charcoal containing mixture to produce a product having an acid value less than 0.1 and an APHA color value less than 30 as determined according to ASTM D1045.

19. The method of claim 15, wherein the 2-ethylhexyl alcohol is present in an amount of 3.5 to 4.5 molar equivalents, based on the total moles of trimellitic acid or trimellitic anhydride or combination thereof.

20. The method of claim 15, wherein the temperature is less than or equal to 250°

C.