Process for the preparation of a tetraalkylcyclobutane-1,3-diol using a promoted nickel-based catalyst
AssigneeEastman Chemical Company
InventorsJennifer Ellen McCusker-Orth, Michael Wayne Salyer
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Abstract
The present invention relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol. In one embodiment, the present invention relates to the production of a 2,2,4,4-tetraalkylcyclobutane-1,3-diol by hydrogenation of a 2,2,4,4-tetraalkylcyclobutane-1,3-dione in the presence of a promoted nickel-based catalyst.
Claims24
A process for producing a 2,2,4,4-tetraalkylcyclobutane-1,3-diol of Formula II, comprising contacting a 2,2,4,4-tetraalkylcyclobutane-1,3-dione with hydrogen in the presence of a promoted nickel-based catalyst under conditions of temperature and pressure sufficient to form a 2,2,4,4-tetraalkylcyclobutane-1,3-diol,
- wherein each of the alkyl radicals R1, R2, R3 and R4 has, independently from each other, 1 to 8 carbon atoms and wherein less than 2 mol % of the 2,2,4,4-tetraalkylcyclobutane-1, 3-dione is converted to ring-open products and wherein the promoted nickel-based catalyst comprises a promoter metal chosen from a Group 4 metal.
A process for producing 2,2,4,4-tetramethylcyclobutane-1,3-diol, comprising contacting 2,2,4,4-tetramethylcyclobutane-1,3-dione, a promoted nickel-based catalyst, a non-protic solvent, and hydrogen in a hydrogenation zone under conditions of temperature and pressure sufficient to form 2,2,4,4-tetramethylcyclobutane-1,3-diol, wherein less than 2 mol % of the 2,2,4,4-tetraalkylcyclobutane-1,3-dione is converted to ring-open products and wherein the promoted nickel-based catalyst comprises a promoter metal chosen from a Group 4 metal.
A process for producing 2,2,4,4-tetramethylcyclobutane-1,3-diol comprising:
- (a) feeding isobutyric anhydride to a pyrolysis zone, wherein the isobutyric anhydride is heated at a temperature of 350° C. to 600° C. to produce a vapor effluent comprising dimethylketene, isobutyric acid, and unreacted isobutyric anhydride;
- (b) cooling the vapor effluent to condense isobutyric acid and isobutyric anhydride and separating the condensate from the dimethylketene vapor;
- (c) feeding the dimethylketene vapor to an absorption zone, wherein the dimethylketene vapor is contacted with a solvent comprising an ester containing 4 to 20 carbon atoms to produce an absorption zone effluent comprising a solution of dimethylketene in the solvent;
- wherein the ester comprises residues of an aliphatic carboxylic acid and an alkanol;
- (d) feeding the absorption zone effluent to a dimerization zone wherein the absorption zone effluent is heated at a temperature of from 70° C. to 140° C. to convert dimethylketene to 2,2,4,4-tetramethylcyclobutane-1,3-dione to produce a dimerization zone effluent comprising a solution of 2,2,4,4-tetramethylcyclobutane-1,3-dione in the solvent;
- and
- (e) contacting the 2,2,4,4-tetramethylcyclobutane-1,3-dione with hydrogen in the presence of a promoted nickel-based catalyst under conditions of temperature and pressure sufficient to form a 2,2,4,4-tetramethylcyclobutane-1, 3-diol, wherein less than 2 mol % of the 2,2,4,4-tetraalkylcyclobutane-1, 3-dione is converted to ring-open products and wherein the promoted nickel-based catalyst comprises a promoter metal chosen from a Group 4 metal.
Dependencies are inferred from the claim text.