Methods of producing dicarbonyl compounds
View Patent ↗Dicarboxylic acids, such as adipic acid, and diesters, such as adipates, may be produced by hydrogenating alkynes that may be produced from raw materials salvaged from waste stream processes. The carbons of the dicarboxylic acids are provided by alkynes generated from biomass waste and carbon dioxide recovered from waste streams such as exhaust gases.
1. A method for producing dicarbonyl compound of formula I:
ROOC—(CH 2 ) n —COOR (I),
wherein R is —H and n=4, the method comprising:
hydrogenating a bis-carbonyl alkyne of formula II:
ROOC—(C n H (2n-4m) —COOR (II),
wherein R is —H, n=4, and m=2, wherein hydrogenating comprises reacting the bis-carbonyl alkyne of formula II with hydrogen gas in the presence of catalyst selected from the group consisting of platinum and palladium, for about 3 h.
2. The method of claim 1 , further comprising carboxylating an alkyne of formula III:
H—(C n H (2n-4m) —H (III),
wherein n=4, m=2, with two equivalents of CO 2 in the presence of a first metal catalyst to produce the bis-carbonyl alkyne of formula II, wherein the first metal catalyst comprises copper, silver, bismuth, or combinations thereof.
3. The method of claim 2 , further comprising preparing the alkyne of formula III by base promoted elimination of hydrogen halide from a dihalo-alkyne of formula IV:
X—(C n H (2n-4z) )—X (IV),
wherein n=4, z=2,
and
each X comprises a same or different one of F, Cl, Br, I, and At.
4. The method of claim 3 , wherein preparing the dihalo-alkyne of formula IV comprises treating an alkyne diol of formula V:
HO—(C n H (2n-4z) )—OH (V)
wherein n=4, z=2, with thionyl halides of formula SOX 2 , wherein each X comprises a same or different one of F, Cl, Br, I, and At.
5. The method of claim 4 , further comprises preparing the alkyne diol of formula V by reacting an alkyne of formula VI:
H—(C (n-2) H (2(n-2)-4z) )—H (VI)
wherein n=4, z=1, with 2 equivalents of formaldehyde in the presence of a second metal catalyst comprising copper, silver, bismuth, or combinations thereof.
6. The method of claim 1 , further comprising producing the bis-carboxy alkyne of formula II: ROOC—(C n H (2n-4m) )—COOR (II), wherein R is —H, n=4, and m=2 by carboxylating diacetylene with CO 2 in the presence of a first metal catalyst including copper, silver, bismuth, or combinations thereof.
7. The method of claim 6 , further comprising producing the diacetylene by base promoted elimination of HCl from 1,4-dihalo-2-butyne.
8. The method of claim 7 , further comprising producing the 1,4-dihalo-2-butyne by treating 2-butyne-1,4-diol with thionyl chloride.
9. The method of claim 8 , further comprising producing the 2-butyne-1,4-diol by contacting acetylene and formaldehyde in the presence of a second metal catalyst including copper, silver, bismuth, or combinations thereof.
10. The method of claim 9 , further comprising producing the acetylene by pyrolysis of lignocellulosic biomass.