Patent ID: 8759544

Claim:
A process for the preparation of a compound of Formula I: named 5-(3,3-dimethylbutyn-1-yl)-3-[(cis-4-hydroxy-4-{[(3S)-tetrahydrofuran-3-yloxy]methyl}cyclohexyl){[(1R)-4-methylcyclohex-3-en-1-yl]carbonyl}amino]thiophene-2-carboxylic acid, or a stereoisomer, mixture of stereoisomers, pharmaceutically acceptable salt or ester thereof, comprising: contacting a compound of Formula IV, named 5-(3,3-dimethylbutyn-1-yl)-3-[(cis-4-hydroxy-4-{[(3S)-tetrahydrofuran-3-yloxy]methyl}cyclohexyl){[(1R)-4-methylcyclohex-3-en-1-yl]carbonyl}amino]thiophene, or a stereoisomer, mixture of stereoisomers, or salt thereof, with a base in the presence of CO 2 : under carboxylation reaction conditions to provide the compound of Formula I or a stereoisomer, mixture of stereoisomers, pharmaceutically acceptable salt or ester thereof.