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Synlett 2013; 24(18): 2389-2392
DOI: 10.1055/s-0033-1339707
letter
© Georg Thieme Verlag Stuttgart · New York

Synthetic Routes toward Asymmetrically Substituted (Functionalized) 4H-Cyclopenta[2,1-b:3,4-b′]dithiophenes

Wouter Vanormelingen
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
,
Pieter Verstappen
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
,
Veronique Maes
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
,
David Bevk
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
,
Laurence Lutsen
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
,
Dirk Vanderzande
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
,
Wouter Maes*
a   Imec-Imomec, Wetenschapspark 1, 3590 Diepenbeek, Belgium
b   Design & Synthesis of Organic Semiconductors (DSOS), Institute for Materials Research (IMO), Hasselt University, Agoralaan 1, Building D, 3590 Diepenbeek, Belgium   Fax: +32(11)268299   Email: wouter.maes@uhasselt.be
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Further Information

Publication History

Received: 31 July 2013

Accepted after revision: 14 August 2013

Publication Date:
03 September 2013 (online)

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Abstract

A two-step synthetic protocol involving (i) a Wittig-type carbonyl olefination, and (ii) regioselective alkylation of the exocyclic double bond with LiAlH4 and an alkyl bromide, was developed as an alternative to the recently reported three-step synthetic approach toward asymmetrically substituted/functionalized 4H-cyclopenta[2,1-b:3,4-b′]dithiophenes. The two routes are rather complementary, with specific advantages depending on the desired substitution pattern, and are of particular appeal for the construction of semiconducting materials to be applied in organic photovoltaics.

Key words

cyclopentadithiophene - Friedel–Crafts cyclization - Wittig reaction - reduction - organic photovoltaics

Supporting Information

    for this article (additional experimental and characterization data, 1H NMR and 13C NMR spectra for the novel CPDTs, and additional data on the ring closure reaction) is available online at http://www.thieme-connect.com/ejournals/toc/synlett.
  • Supporting Information
 

  • References and Notes

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