This paper investigates phase equilibria of interest for the hydroesterification of 10-undecenoic acid methyl ester with methanol and carbon monoxide to dodecanedioic acid dimethyl ester in a solvent system composed of methanol and n-dodecane. Carbon monoxide solubilities were measured in 10-undecenoic acid methyl ester, dodecanedioic acid dimethyl ester, and a mixture of methanol/dodecanedioic acid dimethyl ester at 363 and 393 K and at pressures up to 15 MPa. Vaporliquid equilibrium measurements in the systems methanol/10-undecenoic acid methyl ester, methanol/dodecanedioic acid dimethyl ester, n-dodecane/10-undecenoic acid methyl ester, n-dodecane/dodecanedioic acid dimethyl ester, and 10-undecenoic acid methyl ester/dodecanedioic acid dimethyl ester were performed at temperatures between 342 and 437 K and at pressures of 2 or 80 kPa. The measured data were accurately modeled using the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT).