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CAS Number 255901-50-9

Chemistry Building Blocks, Heterocyclic Building Blocks, Monomers

Product Code B1041-1g
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An analogue of EDOT, its polymer as cathodic electrochromic material with lower oxidation potentials, and greater stability than polythiophene.

3,4-(2,2-Dimethylpropylenedioxy)thiophene (ProDOT-Me2), a 3,4-ethylenedioxythiophene (EDOT) analogue, has a dimethylpropylene side group instead of ethylene while comparing to the EDOT.

3,4-(2,2-Dimethylpropylenedioxy)thiophene was prepared via trans-etherification by refluxing 3,4-dimethoxythiophene with 2,2-dimethylpropane-1,3-diol in toluene by using p-Toluenesulfonic acid as the catalyst. With lower oxidation potentials, and greater stability than polythiophene, conventional cathodic electrochromic material poly(3,4-propylenedioxythiophene) (PProDOT) exhibits very promising electrochromic performance with more rapid switching. Electrochromic window (ECW) based on PPro-DOT-Me2 shows switching speed for colouring and bleaching were almost 0.7 s in a range of +1.5 V to -1.5 V.

Over 10,000 cycles, with 75.7% as the maximum optical modulation and about 5 s as its response time for both colouring and bleaching processes can be achieved for the device with PProDOT-Me2 as the working electrode, bare indium tin oxide as the counter, and AgNO3, LiBr/Br2 as the electrolyte. Three colour states of transparent, blue, and opaque were demonstrated by applying various voltages.

General Information

CAS Number 255901-50-9
Chemical Formula C9H12O2S
Full Name 3,4-(2,2-Dimethylpropylenedioxy)thiophene
Molecular Weight 184.26 g/mol
Synonyms 3,4-Dihydro-3,3-dimethyl-2H-thieno[3,4-b-1,4]dioxepine, ProDOT-Me2
Classification / Family Thiophenes, semiconductor synthesis intermediates, low band gap polymers, OLED, OFETs, organic photovoltaics

Chemical Structure

3,4-(2,2-Dimethylpropylenedioxy)thiophene chemical structure
3,4-(2,2-Dimethylpropylenedioxy)thiophene chemical structure, CAS 255901-50-9

Product Details

Purity >97% (1H NMR in CDCl3)
Melting Point 45.0 °C
Appearance Pale green/off-white powder/crystals

MSDS Documentation

3,4-(2,2-Dimethylpropylenedioxy)thiophene3,4-(2,2-Dimethylpropylenedioxy)thiophene MSDS Sheet

Literature and Reviews

  1. Deterioration mechanism of electrochromic poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) thin films, S. Guan et al., J. Mater. Chem. C, 4, 4584-4591 (2016); DOI: 10.1039/C6TC00930A.
  2. Flexible electrochromic device based on poly (3,4-(2,2-dimethylpropylenedioxy)thiophene), C. Ma et al., Electrochim. Acta, 54 (2), 598-605 (2008); DOI: 10.1016/j.electacta.2008.07.049.
  3. A novel photoelectrochromic device based on poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) thin film and dye-sensitized solar cell, S. Yang et al., Sol. Energy Mater. Sol. Cells, 97, 186-190 (2012); DOI: 0.1016/j.solmat.2011.09.038.
  4. Electrochromic kinetics of nanostructured poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) film on plastic substrate, C. Ma et al., Org. Electron., 12 (6), 980-987 (2011); 10.1016/j.orgel.2011.03.018.
  5. Partly Covered PProDOT-Me2 on MoS2 Nanosheets Counter Electrode for High-Performance Self-Powered Electrochromic Device, M. Khalifa et al., Adv. Mater. Interfaces, 9 (1), 2100945 (2022); DOI:10.1002/admi.202100945.
  6. Fabrication of fast switching electrochromic window based on poly(3,4-(2,2-dimethylpropylenedioxy)thiophene) thin film, R. Lakshmanan et al., J. Mater. Sci.: Mater. Electron. 27, 6035–6042 (2016); DOI: 10.1007/s10854-016-4527-0.
  7. A Transparent to Opaque Electrochromic Device Using Reversible Ag Deposition on PProDOT-Me2 with Robust Stability, K. Sheng et al., Adv. Opt. Mater., 9 (11), 2002149 (2021); DOI: 10.1002/adom.202002149.

To the best of our knowledge the information provided here is accurate. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. Products may have minor cosmetic differences (e.g. to the branding) compared to the photos on our website. All products are for laboratory and research and development use only.

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