Preparation of ¹⁴C₂-cis-1,2-dichloroethylene from ¹⁴C₂-trichloroethylene using a cobalt porphyrin catalyst

A protocol for producing ¹⁴C₂-cis-1,2- dichloroethylene (¹⁴C₂-cis-DCE) from ¹⁴C ₂-trichloroethylene (¹⁴C₂-TCE) was developed as an economical alternative to commercial, custom synthesis of ¹⁴C₂-cis-DCE. The method uses 5,10,15,20-tetrakis-(4- carboxyphenyl) porphyrin cobalt(II) as a catalyst in the presence of titanium(III) citrate to convert ¹⁴C₂-TCE to ¹⁴C₂-cis-DCE as shown in Figure 1. A purge-and-trap technique was used to isolate ¹⁴C₂-cis-DCE to provide a methanolic stock solution of high purity (97% cis-DCE). The overall ¹⁴C₂-cis-DCE yield of the process was approximately 53%.