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Product Code B621-1g
Price £220 ex. VAT

BDTOEHSn, for the synthesis of low bandgap semiconducting polymers

High quality and high purity monomer available online


Specifications | MSDS | Literature and Reviews


4,8-Bis[(2-ethylhexyl)oxy]-2,6-bis(trimethylstannyl)benzo[1,2-b:4,5-b']dithiophene (BDTOEHSn), CAS number 1160823-78-8, is the intermediate for the synthesis of low bandgap semiconducting polymers such as PTB7 and PBDTTPD. Ethylhexyl side chains can help to promote stability and solubility of the target structure or polymer.

Benzo[1,2-b:4,5-b']dithiophene (BDT) is one of the widely used building blocks to produce polymer structures for highly efficient organic solar cells, in a blend with fullerene or non-fullerene acceptors.

General Information


CAS Number 1160823-78-8
Chemical Formula C32H54O2S2Sn2
Molecular Weight 772.32 g/mol
Full Name 4,8-Bis[(2-ethylhexyl)oxy]-2,6-bis(trimethylstannyl)benzo[1,2-b:4,5-b']dithiophene
Synonyms 2,6-Bis(trimethyltin)-4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b′]dithiophene; 1,1′-[4,8-Bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl]bis[1,1,1-trimethyl]stannane
Classification / Family Benzodithiophene (BDT) derivatives, Organic semiconducting materials, Semiconductor Synthesis, Low band gap polymers, Organic Photovoltaics.

Chemical Structure


BDTOEHSn, 1160823-78-8
Chemical structure of 4,8-Bis[(2-ethylhexyl)oxy]-2,6-bis(trimethylstannyl)benzo[1,2-b:4,5-b']dithiophene (BDTOEHSn), CAS 1160823-78-8

Product Details


Purity >98%
Melting Point 70-75 °C
Appearance White crystals/powder

MSDS Documentation


BDTOEHSn MSDSBDTOEHSn MSDS sheet

Literature and Reviews


  1. Improving the long-term stability of PBDTTPD polymer solar cells through material purification aimed at removing organic impurities, W. Mateker et al., Energy Environ. Sci., 6, 2529 (2013); DOI: 10.1039/c3ee41328d.
  2. Interplay Between Side Chain Pattern, Polymer Aggregation, and Charge Carrier Dynamics in PBDTTPD:PCBM Bulk-Heterojunction Solar Cells, C. Dyer-Smith et al., Adv. Energy Mater., 5(9), 1401778 (2015); doi: 10.1002/aenm.201401778.
  3. Absolute Measurement of Domain Composition and Nanoscale Size Distribution Explains Performance in PTB7:PC71BM Solar Cells, B. Collins et al., Adv. Energy Mater., 3(1), 1200377 (2013); DOI:10.1002/aenm.201200377.
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