Synfacts 2006(4): 0340-0340  
DOI: 10.1055/s-2006-932062
Synthesis of Materials and Unnatural Products
© Georg Thieme Verlag Stuttgart · New York

Ring-Closing Metathesis Approach to 3,4-Vinylenedioxythiophenes

Contributor(s): Timothy M. Swager, Anne J. McNeil
P. Leriche*, P. Blanchard*, P. Frère, E. Levillain, G. Mabon, J. Roncali
Université d’Angers, France
Further Information

Publication History

Publication Date:
24 March 2006 (online)

Significance

The unsaturated analogue of EDOT, 3,4-vinylenedioxythiophene (VDOT), is synthesized in a remarkable 55% yield in three steps from commercially available 3,4-dimethoxy­thiophene. The key step utilizes an efficient ruthenium-mediated ring-closing metathesis (RCM) reaction of electron-rich vinyl ethers (W. A. L. van Otterlo, E. L. Ngidi, C. B. de Koning Tetrahedron Lett. 2003, 44, 6483-6486). The dimer, BVDOT, was prepared via oxidative coupling of VDOT. Although BVDOT was successfully electropolymerized, the authors suggest that radical cation delocalization to the alkene in VDOT inhibits its electropolymerization.