Granted Patent B2

US 9,670,134 · App. 14/780,446 · Granted Jun 6, 2017

Abstract

Claims (32)

1. A process for making a compound of formula I:

wherein n is from 0 to 100;

R is H or CH 3 ;

R 1 and R 2 are independently H, linear or branched C 1 -C 8 alkyl optionally substituted with NO 2 , or R 1 R 2 together with the carbon atom to which they are attached form C 3 -C 12 cycloalkyl;

R 3 and R 4 are independently H, linear or branched C 1 -C 8 alkyl, or a group of formula C(R 1 )(R 2 )—O—R 5 , wherein R 5 is H or C(═O)—C(R)═CH 2 , or R 3 and R 4 , together with the carbon atom to which they are attached, form C 3 -C 12 cycloalkyl; and

R 6 and R 7 when present are independently H or CH 3 , the process comprising:

transesterifying a nitroalcohol compound of formula II:

wherein R 1 , R 2 , R 6 , R 7 , and n are the same as in formula I; and

R 3′ and R 4′ are independently H, linear or branched C 1 -C 8 alkyl, or a group of formula C(R 1 )(R 2 )—O—H, or R 3′ and R 4′ , together with the carbon atom to which they are attached, form C 3 -C 12 cycloalkyl,

with a (meth)acrylate of formula III:

wherein R is the same as in formula I; and

R 8 is linear or branched C 1 -C 8 alkyl,

in the presence of a transesterification catalyst and a free radical inhibitor to form the compound of formula I, wherein the transesterification catalyst is a basic catalyst, a zirconium complex, a hafnium complex, or mixtures thereof, and wherein the transesterification is conducted at a temperature of from 70 to 125 ° C. and a pressure of 400 mm Hg to 760 mm Hg.

2. The process of claim 1 wherein the transesterification catalyst is a zirconium complex, a hafnium complex, or a mixture thereof.

3. The process of claim 1 wherein the transesterification catalyst is a hafnium complex.

4. The process of claim 1 wherein the transesterification catalyst is a zirconium complex.

5. The process of claim 1 wherein the mole ratio of (meth)acrylate compound to nitroalcohol is from 1:1 to 20:1.

6. The process of claim 1 wherein excess (meth)acrylate and its corresponding alcohol form an azeotropic mixture and wherein this byproduct alcohol is removed by azeotropic distillation.

7. The process of claim 1 wherein the free-radical inhibitor is, phenothiazine, hydroquinone, methyl ether of hydroquinone, 4-Hydroxy-TEMPO, or mixtures thereof.

8. The process of claim 1 wherein R 1 is H and R 2 is H or linear or branched C 1 -C 8 alkyl optionally substituted with NO 2 .

9. The process of claim 1 wherein R 3′ and R 4′ are independently linear or branched C 1 -C 8 alkyl, or R 3′ and R 4′ , together with the carbon atom to which they are attached, form C 3 -C 12 cycloalkyl.

10. The process of claim 1 wherein the compound of formula I is: 2-methyl-2-nitropropyl acrylate; 2-methyl-2-nitropropyl methacrylate; 2-nitrobutyl acrylate; 2-nitrobutyl methacrylate; 2-methyl-2-nitropropane-1,3-diyl diacrylate; 2-methyl-2-nitropropane-1,3-diyl bis(2-methylacrylate); 3-hydroxy-2-methyl-2-nitropropyl acrylate; 3-hydroxy-2-methyl-2-nitropropyl methacrylate; 2-ethyl-2-nitropropane-1,3-diyl diacrylate; 2-ethyl-2-nitropropane-1,3-diyl bis(2-methylacrylate); 2-(hydroxymethyl)-2-nitrobutyl acrylate; 2(hydroxymethyl)-2-nitrobutyl methacrylate; 3-hydroxy-2-(hydroxymethyl)-2-nitropropyl acrylate; 3-hydroxy-2-(hydroxymethyl)-2-nitropropyl methacrylate; 2-(hydroxymethyl)-2-nitropropane-1,3-diyl diacrylate; 2-(hydroxymethyl)-2-nitropropane-1,3-diyl bis(2methylacrylate); 3-nitrooctan-4-yl acrylate; 3-nitrooctan-4-yl methacrylate; 2-((acryloyloxy)methyl)-2-nitropropane-1,3-diyl diacrylate; 2-((methacryloyloxy)methyl)-2-nitropropane-1,3-diyl bis(2-methylacrylate); 2-methyl-2-nitrobutyl acrylate; 2-methyl-2-nitrobutyl methacrylate; (1-nitrocyclohexyl)methyl acrylate; (1-nitrocyclohexyl)methyl methacrylate; 1-(nitromethyl)cyclohexyl acrylate; 1-(nitromethyl)cyclohexyl methacrylate; 2,5,6-trimethyl-2,6-dinitroheptan-3-yl acrylate; or 2,5,6-trimethyl-2,6-dinitroheptan-3-yl methacrylate, or an alkoxylated derivative thereof.

11. The process of claim 1 wherein R 1 is H and R 2 is H or linear or branched C 1 -C 6 alkyl optionally substituted with NO 2 .

12. The process of claim 1 wherein R 1 is H and R 2 is H.

13. The process of claim 1 wherein R 1 and R 2 together with the carbon atom to which they are attached, form a cyclohexyl group.

14. The process of claim 1 wherein R 3′ and R 4′ together with the carbon atom to which they are attached, form a cyclohexyl group.

15. The process of claim 4 wherein R 1 is H and R 2 is H or R 1 and R 2 together with the carbon atom to which they are attached, form a cyclohexyl group;

the transesterification catalyst is present at a concentration of 0.1 to 10 mol %.; and

n is 0.

16. The process of claim 1 wherein the transesterification catalyst is zirconium acetyl acetonate.

17. The process of claim 1 wherein the transesterification catalyst is a basic catalyst.

18. The process of claim 17 wherein the transesterification catalyst is lithium hydroxide.

Assignments (6)