Dimethyl 2-chloroterephthalate → Dimethyl 2-chloro-cyclohexane-1,4-dicarboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a Parr pressure reactor, a stirred suspension of trans,trans dimethyl muconate (6.1 g, 36 mmol) in dimethyldipropyleneglycol (120 ml, 0.3 M) is heated under vinyl chloride pressure (18 psi (0.124 MPa) at 23° C.) to 165° C. for 48 hours. After cooling to room temperature, the reaction mixture is diluted using the same solvent to 200 ml in a volumetric flask, transferred into a round-bottom flask equipped with a magnetic stirring bar, and Pd/C catalyst is added (360 mg of Johnson-Matthey 5 percent Pd/C #6, 0.2 mol percent) at room temperature. The flask is equipped with a reflux condenser, flitted gas dispersion tube, and internal T probe. Under N2 flow (190 ml/min) and stirring (190 rpm) the mixture is heated to reflux while samples are taken at appropriate intervals (t=0.0, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0 h) to monitor the progress of the reactions occurring. After 8 hour reaction time, dimethyl chloro-terephthalate is present. Some material also undergoes C—Cl bond cleavage and dimethyl 2-chloro-cyclohexane-1,4-dicarboxylate is also formed.

Herkunft & Nachweise