Born-based cycloaddition catalysts and methods for the production of bio-based terephthalic acid, isophthalic acid and poly (ethylene terephthalate)
Methods for producing cycloaddition products comprising: reacting a diene with a dienophile in the presence of one or more boron-based catalysts of Formula I or Formula II are provided. In particular, the methods can be used to prepare 4-methyl-3-cyclohexene-1-carboxylic acid and 3-methyl-3-cyclohexene-1-carboxylic acid, including bio-based versions thereof. The cycloaddition products can be advantageously used in the production of terephthalic acid and isophthalic acid, and ultimately, poly(ethylene terephthalate), and bio-based versions thereof. BOBL 4 Formula II
1. A method for producing a cycloaddition product comprising: reacting a diene with a dienophile in the presence of one or more catalysts of Formula I or Formula II;
wherein a catalyst of Formula I has the following structure:
wherein each X, Y and Z is independently H, F, Cl, Br, I, OC(═O)R 1 , OR 1 , substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 6-12 aryl;
wherein R 1 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl;
wherein at least one of X, Y and Z is Cl; and
wherein the catalyst is not BCl 3 ; and
wherein a catalyst of Formula II has the following structure:
BOBL 4 Formula II
wherein each L is independently selected from the group consisting of OC(═O)R 2 , substituted or unsubstituted C 6-12 aryl, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 5-12 cycloalkyl; substituted or unsubstituted C 1-6 alkylsulfonate; substituted or unsubstituted C 6-12 arylsulfonate, and substituted or unsubstituted C 5-12 heteroaryl; and
wherein R 2 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl;
wherein the dienophile comprises a —CH═CHC(O)OH group.
2. The method of claim 1 , wherein the catalyst of Formula I is selected from the group consisting of Cl 2 B(OC(═O)CH 3 ) and Cl 2 B(OC(═O)CF 3) .
3. The method of claim 1 , wherein the catalyst of Formula II is selected from the group consisting of BOB(OC(═O)CH 3 ) 4 and BOB(C 6 H 5 ) 4 .
4. The method of claim 1 , wherein the one or more catalysts of Formula I or Formula II comprises: BOB(OC(═O)CH 3 ) 4 .
5. The method of claim 1 , wherein one or both of the diene and dienophile are bio-based.
6. The method of claim 1 , wherein the dienophile is a C 3 -C 12 alkene comprising an electron-withdrawing group in conjugation with the alkene.
7. The method of claim 1 , wherein the dienophile is selected from the group consisting of: acrylic acid, a β-acylacrylic acid, and any bio-derived sources thereof.
8. The method of claim 1 , wherein the diene is a C 4 -C 17 hydrocarbon that contains at least two carbon double bonds which are separated by a single bond.
9. The method of claim 8 , wherein the diene is liquid at or near about 20° C. to about 25° C.
10. The method of claim 1 , wherein the cycloaddition product is 4-methyl-3-cyclohexene-1-carboxylic acid.
11. A method for producing 4-methyl-3-cyclohexene-1-carboxylic acid, comprising reacting isoprene with acrylic acid in the presence of one or more catalysts of Formula I or Formula II to produce 4-methyl-3-cyclohexene-1-carboxylic acid;
wherein a catalyst of Formula I has the following structure:
wherein each X, Y and Z is independently H, F, Cl, Br, I, OC(═O)R 1 , OR 1 , substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 6-12 aryl;
wherein R 1 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl; and
wherein at least one of X, Y and Z is Cl; and
wherein the catalyst is not BCl 3 ; and
wherein a catalyst of Formula II has the following structure:
BOBL 4 Formula II
wherein each L is independently selected from the group consisting of OC(═O)R 2 , substituted or unsubstituted C 6-12 aryl, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 5-12 cycloalkyl; substituted or unsubstituted C 1-6 alkylsulfonate; substituted or unsubstituted C 6-12 arylsulfonate, and substituted or unsubstituted C 5-12 heteroaryl; and
wherein R 2 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl.
12. The method of claim 1 , wherein the reaction is conducted at about ambient temperature.
13. The method of claim 11 , wherein the method also produces 3-methyl-3-cyclohexene-1-carboxylic acid.
14. The method of claim 11 , wherein the one or more catalysts of Formula I or Formula II comprises: BOB(OC(═O)CH 3 ) 4 .
15. A method for producing terephthalic acid, isophthalic acid or a mixture thereof, comprising:
(a) reacting isoprene with acrylic acid in the presence of one or more catalysts of Formula I or Formula II to form 4-methyl-3-cyclohexene-1-carboxylic acid, 3-methyl-3-cyclohexene-1-carboxylic acid, or a mixtures thereof;
(b) performing an aromatization reaction on the 4-methyl-3-cyclohexene-1-carboxylic acid, 3-methyl-3-cyclohexene-1-carboxylic acid, or a mixtures thereof to form a second product selected from the group consisting of para-toluic acid, meta-toluic acid, and mixtures thereof; and
(c) performing an oxidation reaction on the second product to form terephthalic acid, isophthalic acid, or mixtures thereof;
wherein a catalyst of Formula I has the following structure:
wherein each X, Y and Z is independently H, F, Cl, Br, I, OC(═O)R 1 , OR 1 , substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 6-12 aryl;
wherein R 1 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl;
wherein at least one of X, Y and Z is Cl; and
wherein the catalyst is not BCl 3 ; and
wherein a catalyst of Formula II has the following structure:
BOBL 4 Formula II
wherein each L is independently selected from the group consisting of OC(═O)R 2 , substituted or unsubstituted C 6-12 aryl, substituted or unsubstituted C 1-6 alkyl, substituted or unsubstituted C 5-12 cycloalkyl; substituted or unsubstituted C 1-6 alkylsulfonate; substituted or unsubstituted C 6-12 arylsulfonate, and substituted or unsubstituted C 5-12 heteroaryl; and
wherein R 2 is a substituted or unsubstituted C 1-6 alkyl; or a substituted or unsubstituted C 6-12 aryl.
16. The method of claim 15 , wherein the one or both of isoprene and acrylic acid are bio-based.
17. The method of claim 15 , wherein the aromatization reaction is conducted in the presence of sulfuric acid.
18. The method of claim 15 , wherein the aromatization reaction is performed in acetic anhydride solvent.
19. The method of claim 15 , wherein the aromatization reaction is conducted in the presence of a catalyst, optionally selected from the group consisting of chromium, molybdenum, iridium, rhodium, ruthenium, nickel, palladium, platinum, vanadium, iron and manganese.
20. The method of claim 15 , wherein the one or more catalysts of Formula I or Formula II comprises: BOB(OC(═O)CH 3 ) 4 .