Synthesis of 2-(4-chlorophenyl)-2-(4-chloro-3-thiophenol)-1,1-dichloroethene (3-SH-DDE) via Newman-Kwart rearrangement - A precursor for synthesis of radiolabeled and unlabeled alkylsulfonyl-DDEs
2009 (English)In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, ISSN 0045-6535, Vol. 76, no 6, 805-810 p.Article in journal (Refereed) Published
For the first time, a pathway for synthesis of 2-(4-chlorophenyl)-2-(4-chloro-3-thiophenol)-1,1-dichloroethene (3-SH-DDE), is presented. The compound is of particular interest as a precursor for synthesis of alkylsulfonyl-DDE containing different alkyl groups to discover structural activity relationships, and to promote synthesis of radiolabeled methylsulfonyl-DDE. 2-Chloro-5-methyl phenol was first methylated and further oxidized to the corresponding benzoic acid. The acid was reduced to the corresponding aldehyde (4-chloro-3-methoxy benzaldehyde) via 4-chloro-3-methoxy-benzene methanol. A lead/aluminium bimetal system was used to carry out the reductive addition of tetrachloromethane to 4-chloro-3-methoxy benzaldehyde to obtain 2,2,2-trichloro-1-(4-chloro-3-methoxyphenyl)ethanol,the desired starting material to synthesize the DDT-analogue (2-(4-chlorophenyl)-2-(4-chloro-3-methoxy-phenyl)-1,1,1-trichloroethane). Elimination of hydrochloric acid and removal of the methyl group led to the 3-OH-DDE. The Newman-Kwart rearrangement was applied to convert 3-OH-DDE to 3-SH-DDE via the dimethyl-carbarnothioate derivative. 3-SH-DDE is then used as a precursor for the radiolabel synthesis. The overall yield to acquire 3-SH-DDE after 11 steps was 3%. The step with the lowest yield was the DDT-analog synthesis with a yield of 30%. All other step had a yield of >50%. 3-SH-DDE was methylated with C-14-labeled iodomethane and oxidized by hydrogen peroxide to obtain 3-[C-14]MeSO2-DDE in an overall yield of 30%.
Place, publisher, year, edition, pages
Oxford: PERGAMON-ELSEVIER SCIENCE LTD , 2009. Vol. 76, no 6, 805-810 p.
Methyl sulfone metabolites, Aromatic substitution, Eastern Slovakia, Human milk, Aryl, PCBS, 3-Methylsulfonyl-DDE, Mechanism, Sulfides, P, P'-DDE
Research subject Environmental Chemistry
IdentifiersURN: urn:nbn:se:su:diva-35800DOI: 10.1016/j.chemosphere.2009.04.042ISI: 000269243900012OAI: oai:DiVA.org:su-35800DiVA: diva2:288071