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CAS Number 389-58-2

Chemistry Building Blocks, Heterocyclic Building Blocks, Materials, Monomers

Product Code B271-1g
Price £170 ex. VAT

High purity CPDT monomer used in OFETs and organic electronics

Available online for fast, secure dispatch

4H-cyclopenta[2,1-b:3,4-b′]dithiophene, also known as CPDT (CAS number 389-58-2), a rigid coplanar structure favouring π−π intermolecular interactions with good electron-donating properties, has been one of the most attractive building blocks for organic field effect transistors and organic electronics. The five-member ring in the middle also offer the function to have side-chain manipulation to enhance solubility in solutions for device fabrications, morphology and polymer processing. One of the intensively studied polymers for organic electronics, PCPDTBT, with the alternating CPDT and 2,1,3- benzothiadiazole (BT) units, has demonstrated device performance of PCE over 6% [5]

Recently, the CPDT backboned polymer, CPE-K, has been incorporated as the electron hole transporting layer (HTL) in the polymer/fullerene BHJ and perovskite solar cells. The devices using CPE-K HTL show competitive performance compared with that using PEDOT:PSS HTL. As an alternative to PEDOT:PSS, the use of CPE-K as an organic hole transport material enables the formation of uniform perovskite films with complete surface coverage for an efficient, stable perovskite/fullerene planar heterojunction solar cell [1, 2]

4H-cyclopenta[2,1-b:3,4-b′]dithiophene is the intermediate for the synthesis of 4,4'-alkyl-cyclopenta[2,1-b:3,4-b′]dithiophene [6].

synthesis of 4,4'-alkyl-cyclopenta[2,1-b:3,4-b′]dithiophene
Synthesis of 4,4'-alkyl-cyclopenta[2,1-b:3,4-b′]dithiophene in aqueous solutions
A synthesis precusor

A synthesis precusor

For cyclopentadithiophene backboned polymers

Cyclopentadithiophene building block

Cyclopentadithiophene building block

For semiconductors, OFETs, and solar cells

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High purity 389-58-2

High purity

>99% High purity

General Information

CAS Number
Chemical Formula C9H6S2
Molecular Weight 178.27 g/mol
Synonym 4H-Cyclopenta[2,1-b:3,4-b']dithiophene
Classification / Family Monomers, Building blocks, Heterocycles, Chemical synthesis for low-band gap polymers, Thiophene, Intermediates for high performance Organic Photovoltaics, OFETs, Polymer solar cells

Chemical Structure

Chemical structure of 4H-Cyclopenta[2,1-b:3,4-b']dithiophene CAS 389-58-2
Chemical structure of 4H-Cyclopenta[2,1-b:3,4-b']dithiophene, CAS 389-58-2

Product Details

Purity >99%
Melting Point 71.0 °C - 75.0 °C
Appearance Off-white powder

NMR Characterisation

1H NMR cyclopenta-bithiophene
1H NMR spectrum of 4H-Cyclopenta[2,1-b:3,4-b']dithiophene in CDCl(view full version)

MSDS Documentation

4H-Cyclopenta[1,2-b:5,4-b']dithiophene MSDS4H-Cyclopenta[1,2-b:5,4-b']dithiophene MSDS sheet

Literature and Reviews

  1. Conjugated polyelectrolyte hole transport layer for inverted-type perovskite solar cells, H. Choi et al., Nat. Commun., DOI: 10.1038/ncomms8348, 6, 7348 (2015)
  2. Conductive conjugated polyelectrolyte as hole-transporting layer for organic bulk heterojunction solar cells, H. Zhou, et al., Adv. Mater. , 26, 780–785(2014)
  3. Improved Photovoltaic Performance of a Semicrystalline Narrow Bandgap Copolymer Based on 4H-Cyclopenta[2,1-b:3,4- b′]dithiophene Donor and Thiazolo[5,4-d]thiazole Acceptor Units, S. V. Mierloo et al., Chem. Mater., 24, 587−593 (2012).
  4. Synthesis and characterization of a series of low-bandgap copolymers based on cyclopenta[2,1-b:3,4-b']dithiophene and thienopyrroledione for photovoltaic applications, Y-R. Hong et al., Solar Energy Materials & Solar Cells 102, 58–65 (2012)
  5. Alternating Copolymers of Cyclopenta[2,1-b;3,4-b´]dithiophene and Thieno[3,4-c]pyrrole-4,6-dione for High-Performance Polymer Solar Cells, Z. Li, et al., Adv. Func. Mater., 21, 3331–3336(2011)
  6. Highly efficient and facile alkylation of 4Hcyclopenta-[2,1-b:3,4-b0]dithiophene in water, T. B. Raju et al., RSC Adv., 4, 37738 (2014).

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