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CAS Number 255901-50-9

Chemistry Building Blocks, Heterocyclic Building Blocks, Materials, Monomers

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Product Code B1041-1g
Price £190 ex. VAT


An analogue of EDOT, its polymer as cathodic electrochromic material with lower oxidation potentials, and greater stability than polythiophene.

Specifications | MSDS | Literature and Reviews

3,4-(2,2-Dimethylpropylenedioxy)thiophene (ProDOT-Me2, CAS number 255901-50-9), 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.
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