175658-90-9

Basic information

• Product Name: 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene
• Synonyms: 2,5-Bis(trimethylsilyl)dibromothiophene;3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene;(3,4-DIBROMOTHIOPHENE-2,5-DIYL)BIS(TRIMETHYLSILANE);3,4-Dibromo-2,5-thienediyl)bis(trimethylsilane
• CAS NO: 175658-90-9
• Molecular Formula: C10H18Br2SSi2
• Molecular Weight: 386.29392
• Mol File: 175658-90-9.mol
• Article Data: 10

Chemical Properties

• Boiling Point: 306℃
• Flash Point: 139℃
• Appearance: /
• Density: 1.40
• CAS DataBase Reference: 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene(CAS DataBase Reference)
• NIST Chemistry Reference: 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene(175658-90-9)
• EPA Substance Registry System: 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene(175658-90-9)

Safety Data

• Hazardous Substances Data: 175658-90-9(Hazardous Substances Data)

Usage

General Description

3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene is a chemical compound with the molecular formula C12H17Br2SSi2. It is a derivative of thiophene, a five-membered heterocyclic compound containing sulfur. 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene is unique in that it contains both bromine and trimethylsilyl groups attached to the thiophene ring. It is often used in organic synthesis as a building block for the production of various organic compounds. Additionally, its silyl group makes it versatile for use as a protecting group in organic chemistry reactions, allowing for selective manipulation of functional groups in a molecule. Overall, 3,4-Dibromo-2,5-bis(trimethylsilyl)thiophene is an important chemical reagent in organic chemistry with a wide range of applications.

Upstream product

• 3141-27-3 2,5-dibromothiophen 
• 75-77-4 chloro-trimethyl-silane 
• 112051-54-4 3,5-dibromo-2-(trimethylsilyl)thiophene 
• 3958-03-0 Tetrabromothiophene 
• 3141-26-2 3,4-dibromothiophene 

Downstream Products

• 17906-71-7 2,5-bis(trimethylsilyl)thiophene 
• 347838-12-4 3,4-difluorothiophene-2,5-diyl-bis(trimethylsilane) 

Relevant articles and documents

Utilizing Difluorinated Thiophene Units to Improve the Performance of Polymer Solar Cells

While there are numerous approaches to functionalize conjugated polymers for organic solar cells (OSCs), one widely adopted approach is fluorination. Of the many different locations for fluorination, one of the least studied is the conjugated linker which connects the donor and acceptor moieties; further, all existing reports primarily explore monofluorinated thiophene units. Herein, we synthesize and compare two conjugated polymers, HTAZ and DFT-HTAZ, which have different thiophene linkers. In HTAZ, a bare thiophene unit connects the donor and acceptor moieties, while DFT-HTAZ utilizes difluorinated thiophene (DFT) linkers. These polymers serve as the model system to explore the impact of DFT units in OSCs; additionally, this is the first publication to investigate polymers containing DFT units paired with non-fullerene acceptors. Compared to HTAZ, the incorporation of the DFT units maintained the optical properties while lowering the energy levels by a0.4 eV, which allowed for a much improved Voc value of a1 V. Importantly, when compared with the appropriate non-fullerene acceptor, DFT-HTAZ:ITIC-Th1 blends reached an efficiency of a10%, which is nearly 3× that of the nonfluorinated HTAZ. As most OSC polymers have thiophene linkers, using DFT units could serve as a proficient method to increase OSC performance in many polymer systems, especially those that do not have locations for functionalization on the acceptor moiety.

Regiospecific silylation of 2,5-dibromothiophene: A reinvestigation

Lithiation of 2,5-dibromothiophene by LDA with ensuing silylation proceeds regiospecifically in accordance with the halogen dance mechanism to yield 3,5-dibromo-2-trimethylsilylthiophene or 3,4-dibromo-2,5-bis(trimethylsilyl)thiophene depending on the ratio of reagents. The outcome of the reaction was confirmed by further chemical transformations of the latter compound to 2,5-bis(trimethylsilyl)thiophene and 2,5-bis(trimethylsilyl)thiophene-1,1-dioxide. The structures of the compounds obtained were determined by 1H, 13C and 29Si NMR, and X-ray analysis in the case of a sulfone.

Isoindigo-3,4-Difluorothiophene Polymer Acceptors Yield “All-Polymer” Bulk-Heterojunction Solar Cells with over 7 % Efficiency

Poly(isoindigo-alt-3,4-difluorothiophene) (PIID[2F]T) analogues used as “polymer acceptors” in bulk-heterojunction (BHJ) solar cells achieve >7 % efficiency when used in conjunction with the polymer donor PBFTAZ (model system; copolymer of benzo[1,2-b:4,5

Influence of backbone fluorination in regioregular poly(3-alkyl-4-fluoro)thiophenes

We report two strategies toward the synthesis of 3-alkyl-4-fluorothiophenes containing straight (hexyl and octyl) and branched (2-ethylhexyl) alkyl groups. We demonstrate that treatment of the dibrominated monomer with 1 equiv of alkyl Grignard reagent leads to the formation of a single regioisomer as a result of the pronounced directing effect of the fluorine group. Polymerization of the resulting species affords highly regioregular poly(3-alkyl-4-fluoro)thiophenes. Comparison of their properties to those of the analogous non-fluorinated polymers shows that backbone fluorination leads to an increase in the polymer ionization potential without a significant change in optical band gap. Fluorination also results in an enhanced tendency to aggregate in solution, which is ascribed to a more co-planar backbone on the basis of Raman and DFT calculations. Average charge carrier mobilities in field-effect transistors are found to increase by up to a factor of 5 for the fluorinated polymers.