Patent ID: 9238602
Filing Date: 2016-01-19
CPC Classification: C07B,C07C

Claim Text:
1. A process for the preparation of cis-2,2,4,4-tetramethylcyclobutane-1,3-diol, the process comprising: contacting a monomer selected from 2,2,4,4-tetramethylcyclobutane-1,3-dione, 3-hydroxy-2,2,4,4-tetramethylcyclobutanone, 2,2,4,4-tetramethylcyclobutane-1,3-diol having a starting cis:trans molar ratio of 0:1 to about 2:1, or mixtures thereof with hydrogen in the presence of a reaction solvent in which the resulting cis-2,2,4,4-tetramethylcyclobutane-1,3-diol is partially soluble, and further in the presence of a catalyst comprising about 0.1 to about 10 weight percent ruthenium, based on the total weight of the catalyst, deposited on a support material, under reaction conditions sufficient to produce a 2,2,4,4-tetramethylcyclobutane-1,3-dial having a final cis:trans molar ratio of from 2:1 to about 25:1, wherein the thermodynamic cis/trans 2,2,4,4-tetramethylcyclobutane-1,3-diol ratio produced by the reaction is greater than the cis/trans 2,2,4,4-tetramethylcyclobutane-1,3-diol solubility ratio in the reaction solvent, and wherein the cis-2,2,4,4-tetramethylcyclobutane-1,3-diol isomer concentration in the reaction solvent is greater than the cis-2,2,4,4-tetramethylcyclobutane-1,3-diol solubility at the reaction temperature.