1 3 cyclopentanediol

1,3-Cyclopentanediol from Sigma Aldrich was obtained as an cis/trans enantiomeric mixture having >95% purity. The commercial batch was analyzed prior to use via NMR and chiral GC to determine the cis/trans ratio, and was found to be 15/85 cis/trans (see ESI for analysis†). Based on the different boiling point of the cis/trans enantiomers, the commercial batch was purified by fractional distillation under vacuum. Various cis/trans ratios were obtained via batch-wise fractional distillation; Generally, 1,3-Cyclopentanediol was loaded in a 50 mL 2-neck round-bottom flask, equipped with a 10 cm vigreux column, distillation 3-way adapter, condenser path, and a vacuum adapter to collect different fractions. Temperature of the oil-bath was varied from 130 °C to 160 °C. Temperature of the boiling phase was measured in the 3-way adapter, and the depth of the vacuum was noted. All fractions were obtained either as colorless liquids or as colorless solids: 7.6% cis (110 °C, 0.85 mbar), 14% cis (125 °C, 1.4 mbar), 20.7% cis (120 °C, 1.6 mbar), 30% cis (116 °C, 1.2 mbar), 41% cis (111 °C, 1.3 mbar).

1,3-Cyclopentanediol (15/85 cis/trans), 1,4-cyclohexanedimethanol (38/62 cis/trans), adipoyl chloride, sebacoyl chloride, terephthaloyl chloride, tin(ii) 2-ethyl-hexanoate, and anhydrous chloroform, DMF, THF, and toluene were obtained from Sigma Aldrich. Magnesium(iv) sulfate, 4-dimethylaminopyridine and pyridine were obtained from ACROS. 2,5-Furan-dicarboxylic acid was obtained from ABCR. 1,4-Cyclohexanediol (46/54 cis/trans) was obtained from Alfa Aesar. Ethylene glycol was obtained from TCI. Standard laboratory solvents were obtained from Biosolve. Deuterated solvents were obtained from Buchem BV (Netherlands). The purchased compounds were used directly without further purification, unless otherwise specified.