Related Experiment Video
Updated: Aug 5, 2025

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Modulating the Alkylation Position on Terminal Thiophene Ring of Naphtho[2,3-b:6,7-b'] Bithieno[2,3-d] Thiophene
Zhongwei Liu1, Ting Jiang2, Yanru Li1
1Institute of Molecular Plus, Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin 300072, China.
Abstract:
Several thiophene terminated thienoacenes with high mobilities in organic thin-film transistors (OTFTs) have been reported; however, the structure-property relationship of thiophene terminated thienoacenes was unclear, especially the impact of α or β position substitution of terminal thiophene ring on molecular packing and physicochemical properties. Here, we report the synthesis and characterization of a six-ring-fused naphtho[2,3-b:6,7-b'] bithieno[2,3-d] thiophene (NBTT) and its derivatives 2,8-dioctyl-naphtho[2,3-b:6,7-b'] bithieno [2,3-d] thiophene (2,8-C8NBTT) and 3,9-dioctyl-naphtho[2,3-b:6,7-b'] bithieno [2,3-d] thiophene (3,9-C8NBTT). It is found that the alkylation on terminal thiophene ring can effectively tune the molecular stacking from a cofacial herringbone stacking mode (NBTT) to layer-by-layer packing (2,8-C8NBTT and 3,9-C8NBTT). Impressively, a hopping to "band-like" charge transport mechanism evolution of vacuum deposited films is realized by modulating the alkylation position on the terminal thiophene rings. As a result, the OTFTs based on 2,8-C8NBTT characterized by a "band-like" transport presents the highest mobility of 3.58 cm2 V-1 s-1 together with a remarkably high current on/off ratio around 109. Furthermore, organic phototransistors (OPTs) based on 2,8-C8NBTT thin film also exhibits higher photosensitivity (P) of 2.0 × 108, photoresponsivity (R) of 3.3 × 103 A W-1, and detectivity (D*) of 1.3 × 1016 Jones than those based on NBTT and 3,9-C8NBTT.
More Related Videos
08:29Morphology Control for Fully Printable Organic–Inorganic Bulk-heterojunction Solar Cells Based on a Ti-alkoxide and Semiconducting Polymer
Published on: January 10, 2017
14:37Ambient Method for the Production of an Ionically Gated Carbon Nanotube Common Cathode in Tandem Organic Solar Cells
Published on: November 5, 2014
Related Concept Videos
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Directing and Steric Effects in Disubstituted Benzene Derivatives
meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H
Radical Substitution: Allylic Bromination
Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.