Process for preparing 4-aminodiphenylamine intermediates
View Patent ↗The invention is directed to a method of producing one or more 4-aminodiphenylamine intermediates comprising the steps: a. bringing an aniline or aniline derivative and nitrobenzene into reactive contact; and b. reacting the aniline and nitrobenzene in a confined zone at a suitable time and temperature, in the presence of a mixture comprising a strong organic base, or equivalent thereof, and an oxidant comprising hydrogen peroxide in an amount of from about 0.01 to about 0.60 moles of hydrogen peroxide to moles of nitrobenzene.
1. A method of producing 4-aminodiphenylamine or a 4-aminodiphenylamine derivative, the method comprising the steps of:
a. contacting an aniline or aniline derivative and nitrobenzene;
b. reacting the aniline or aniline derivative and nitrobenzene in the presence of a strong organic base and an oxidant comprising hydrogen peroxide in an amount of about 0.01 to about 0.60 moles of hydrogen peroxide to moles of nitrobenzene to form a 4-aminodiphenylamine intermediate; and
c. reducing the 4-aminodiphenylamine intermediate in a reduction reaction to produce 4-aminodiphenylamine.
2. The method of claim 1 , wherein the aniline or aniline derivative and nitrobenzene are brought into contact in the presence of the strong base before contacting the aniline or aniline derivative and the nitrobenzene with the oxidant.
3. The method of claim 2 , wherein the temperature of the aniline or aniline derivative and nitrobenzene is increased to at least about 65° C. prior to contact with the hydrogen peroxide.
4. The method of claim 1 , wherein the aniline or aniline derivative is reacted with nitrobenzene at a molar ratio of aniline or aniline derivative to nitrobenzene of about 5.5 or lower.
5. The method of claim 1 , further comprising the step of reductively alkylating the 4-aminodiphenylamine to form an alkylated derivative of the 4-aminodiphenylamine.
6. The method of claim 1 , wherein the aniline or aniline derivative and nitrobenzene are reacted in a mixture comprising the strong organic base and the oxidant comprising hydrogen peroxide in an amount of from about 0.01 to about 0.20 moles of hydrogen peroxide per mole of nitrobenzene.
7. The method of claim 6 , wherein the mixture comprises from about 0.020 to about 0.064 moles of the hydrogen peroxide per mole of nitrobenzene.
8. The method of claim 1 , wherein the reaction temperature in step (b) is from about 65° C. to about 90° C.
9. The method of claim 1 , wherein the hydrogen peroxide is supplied as an aqueous solution comprising from about 3 wt. % to about 5 wt. % hydrogen peroxide.
10. The method of claim 1 , wherein the strong base is tetramethylammonium hydroxide.
11. The method of claim 1 , wherein the hydrogen peroxide is supplied as an aqueous solution comprising from about 3 wt. % to about 7 wt. % hydrogen peroxide in an amount of from about 0.01 to about 0.5 moles of hydrogen peroxide to moles of nitrobenzene.
12. The method of claim 1 , wherein the hydrogen peroxide is supplied as an aqueous solution comprising from about 15 wt. % to about 25 wt. % hydrogen peroxide in an amount of from about 0.01 to about 0.45 moles of hydrogen peroxide to moles of nitrobenzene.
13. The method of claim 1 wherein the hydrogen peroxide is supplied as an aqueous solution comprising from about 25 wt. % to about 40 wt. % hydrogen peroxide in an amount of from about 0.01 to about 0.35 moles of hydrogen peroxide to moles of nitrobenzene.
14. The method of claim 1 , wherein the strong base is recycled from the products of the reduction reaction and contacted with the aniline or aniline derivative and nitrobenzene.
15. The method of claim 14 , wherein the nitrobenzene has a feed time of about 100 minutes or less.
16. The method of claim 15 wherein the reaction temperature is from about 65° to about 90° C.
17. A method of producing a rubber product comprising the steps of:
a. contacting an aniline or aniline derivative and nitrobenzene;
b. reacting the aniline or aniline derivative and nitrobenzene in the presence of a strong organic base and an oxidant comprising hydrogen peroxide to form a 4-aminodiphenylamine intermediate in the absence of a strong inorganic base;
c. reducing the 4-aminodiphenylamine intermediate in a reduction reaction to produce 4-aminodiphenylamine;
d. reductively alkylating the 4-aminodiphenylamine to form an alkylated derivative of the 4-aminodiphenylamine; and
e. incorporating the alkylated derivative of the 4-aminodiphenylamine into a rubber product.
18. The method of claim 17 , wherein the aniline or aniline derivative and nitrobenzene are brought into contact in the presence of the strong base before contacting the aniline or aniline derivative and nitrobenzene with the oxidant.
19. The method of claim 17 , wherein the aniline or aniline derivative is reacted with nitrobenzene at an aniline or aniline derivative to nitrobenzene molar ratio of 5.5 or lower.
20. A composition comprising aniline or aniline derivative, nitrobenzene, a strong organic base in the absence of a strong inorganic base and hydrogen peroxide in an amount of about 0.01 to about 0.60 moles of hydrogen peroxide to moles of nitrobenzene.
21. The composition of claim 20 , where the composition further comprises water.
22. The composition of claim 21 , where the composition comprises no more than about 0.35% wt phenazine.
23. The composition of claim 21 , where the strong organic base comprises tetramethyammoniumhydroxide (TMAH).
24. The method of claim 17 , where the hydrogen peroxide is supplied as an aqueous solution comprising from about 3 wt. % to about 50 wt. % hydrogen peroxide.
25. The method of claim 24 , where the hydrogen peroxide is supplied in an amount of from about 0.01 to about 0.6 moles of hydrogen peroxide to moles of nitrobenzene.
26. A method of producing 4-aminodiphenylamine or a 4-aminodiphenylamine derivative, the method comprising the steps of:
a. contacting an aniline or aniline derivative and nitrobenzene;
b. reacting the aniline or aniline derivative and nitrobenzene in the presence of a strong organic base and an oxidant comprising hydrogen peroxide and supplied as an aqueous solution comprising from about 3 wt. % to about 50 wt. % hydrogen peroxide to form a 4-aminodiphenylamine intermediate; and
c. reducing the 4-aminodiphenylamine intermediate in a reduction reaction to produce 4-aminodiphenylamine.
27. The method of claim 26 , where the hydrogen peroxide is provided in an amount of about 0.01 to about 0.60 moles of hydrogen peroxide to moles of nitrobenzene.
28. The method of claim 27 , where the hydrogen peroxide and supplied as an aqueous solution comprising from about 15 wt. % to about 40 wt. % hydrogen peroxide and in an amount of about 0.04 to about 0.60 moles of hydrogen peroxide to moles of nitrobenzene.