Strong-acid cation exchange resins
View Patent ↗A strong-acid cation exchange resin comprising a plurality of acid groups which are partially neutralized with a cation of formula (I); wherein R 1 at each occurrence independently is hydrogen or a Ci-4-alkyl group, R 2 at each occurrence independently is hydrogen, alkyl or aryl, R 3 at each occurrence independently is hydrogen or alkyl or two vicinal groups R 3 together form an aromatic ring, m is 1, 2, 3, 4, 5 or 6, n is 1, 2, 3 or 4, o is 1 or 2, and p is 1, 2 or 3, is useful in the production of bisphenols.
1. A strong-acid cation exchange resin comprising a plurality of acid groups being partially neutralized with a cation of formula I
wherein
R 1 at each occurrence independently is hydrogen or a C 1-4 -alkyl group,
R 2 at each occurrence independently is hydrogen, alkyl or aryl,
R 3 at each occurrence independently is hydrogen or alkyl or two vicinal groups R 3 together form an aromatic ring,
m is 1, 2, 3, 4, 5 or 6,
n is 1, 2, 3 or 4,
o is 1 or 2, and
p is 1, 2 or 3.
2. The strong-acid cation exchange resin of claim 1 wherein o is 1.
3. The strong-acid cation exchange resin of claim 1 wherein each group R 1 is methyl.
4. The strong-acid cation exchange resin of claim 1 wherein n is 1.
5. The strong-acid cation exchange resin of claim 1 wherein m is 2.
6. The strong-acid cation exchange resin of claim 1 wherein R 2 in each occurrence is hydrogen.
7. The strong-acid cation exchange resin of claim 1 wherein R 3 in each occurrence is hydrogen.
8. The strong-acid cation exchange resin of claim 1 wherein p is 2 or 3.
9. A process for partially neutralizing a strong-acid cation exchange resin comprising contacting a strong-acid ion exchange resin in acid form with a compound of formula II
wherein
R 2 at each occurrence independently is hydrogen, alkyl or aryl,
R 3 at each occurrence independently is hydrogen or alkyl or two vicinal groups R 3 together form an aromatic ring,
R 4 is R 6 —C(O)—NH— or (X z− ) 1/z (R 1 ) p (R 8 ) 3-p N + —
R 5 is hydrogen or —C(O)—R 7 ,
R 1 at each occurrence independently is hydrogen or a C 1-4 -alkyl group,
R 6 and R 7 each independently are a C 1-4 -alkyl group,
R 8 is a group of formula III
X z− is an anion,
m is 1, 2, 3, 4, 5 or 6,
n is 1, 2, 3 or 4,
o is 1 or 2,
p is 1, 2 or 3, and
z is 1, 2, 3 or 4.
10. The process of claim 9 wherein R 4 is (X z− ) 1/z (R 1 ) 3 N + —.
11. The process of claim 9 wherein R 5 is —C(O)—R 7 .
12. The process of claim 9 for producing a strong-acid cation exchange resin of claim 1 .
13. A process for producing a bisphenol wherein a phenolic compound is reacted with a carbonyl compound in the presence of a strong-acid cation exchange resin of claim 1 or in the presence of a strong-acid cation exchange resin produced according to the process of claim 9 .
14. A process for isomerizing by-products resulting from the production of a bisphenol by reaction of a phenolic compound with a carbonyl compound wherein the by-products are contacted with a strong-acid cation exchange resin of claim 1 or with a strong-acid cation exchange resin produced according to the process of claim 9 .