Structural Characterization and Surface Modification of Evaporated Thin Films of 5,5‘‘‘-Bis(aminomethyl)-2,2‘:5‘,2‘‘:5‘‘,2‘‘‘-quaterthiophene and Its Dihydrochloride

Abstract

Thin films of 5,5′′′-bis(aminomethyl)-2,2′:5′,2′′:5′′,2′′′-quaterthiophene (1) and its dihydrochloride (2), both of which possess active amino groups at both the molecular terminals, have been fabricated by direct evaporation deposition. IR and XPS analyses have revealed that these thin films are deposited without causing chemical degradation during the course of deposition. Of these, the thin film of 1 is characterized by the molecular layered structure that can be noticed for the oligothiophene compounds widely, and in this structure the molecular long axis of 1 is nearly vertical to the substrate plane. On the other hand, the film of 2 turned out to be amorphous. The structure of 1 immediately means the presence of a densely packed array of the amino groups at the thin film surface. Making use of this structure, we tried surface modification of the thin film of 1 with an aldehyde. The resulting film was analyzed by XPS spectroscopy, and as a consequence, we confirmed that the surface modification is successfully achieved. Furthermore, we attempted immobilization of glucose oxidase (GOD) onto the thin film of 1 and examined its catalytic activity.

Naphthalenetetracarboxylic Diimide-Based n-Channel Transistor Semiconductors: Structural Variation and Thiol-Enhanced Gold Contacts

“…As discussed in an earlier communication, devices could be fabricated from 1 by deposition of the semiconductor from an aromatic solvent. In addition, compound 6 is soluble and castable in n -butanol, a nonaromatic and less toxic solvent, and its OH groups (and those of 11 ) could act as attachment sites for a biological molecule, as suggested previously for an amino-substituted thiophene derivative …”

Design, Structure, and Optical Properties of Organic−Inorganic Perovskites Containing an Oligothiophene Chromophore

“…The starting AEQT·2HX salts were prepared using a technique similar to that described in detail for the synthesis of 5,5‘ ‘‘-bis(aminomethyl)-2,2‘:5‘,2‘ ‘:5‘ ‘,2‘ ‘‘-quaterthiophene dihydrochloride (AMQT·2HCl) . The intermediate 5,5‘ ‘‘-bis[(2,2,5,5-tetramethyl-1-aza-2,5-disila-1-cyclopentyl)ethyl]-2,2‘:5‘,2‘ ‘:5‘ ‘,2‘ ‘‘-quaterthiophene was first synthesized , and then reacted in a chloroform solution with HX to form a yellow precipitate of the desired AEQT·2HX salt. The IR spectrum of each compound (in a pressed KBr pellet) is consistent with that reported for similar quaterthiophene salts .…”

“…The intermediate 5,5‘ ‘‘-bis[(2,2,5,5-tetramethyl-1-aza-2,5-disila-1-cyclopentyl)ethyl]-2,2‘:5‘,2‘ ‘:5‘ ‘,2‘ ‘‘-quaterthiophene was first synthesized , and then reacted in a chloroform solution with HX to form a yellow precipitate of the desired AEQT·2HX salt. The IR spectrum of each compound (in a pressed KBr pellet) is consistent with that reported for similar quaterthiophene salts . IR for AEQT·2HCl: γ(CH) 791, ν(ring) 1439, δ(NH 3 + ) 1599, ν(NH 3 + ) 2400−3200 cm -1 .…”

Structural and Conformational Studies of Quaterthiophenes Having Extra Bulky Terminal Groups

“…The compounds investigated in the present studies are 5,5‘‘‘-bis[(2,2,5,5-tetramethyl-1-aza-2,5-disila-1-cyclopentyl)methyl]-2,2‘:5‘,2‘‘:5‘‘,2‘‘‘-quaterthiophene ( 1 ), 5,5‘‘‘-bis[(2,2,5,5-tetramethyl-1-aza-2,5-disila-1-cyclopentyl)ethyl]-2,2‘:5‘,2‘‘:5‘‘,2‘‘‘-quaterthiophene ( 2 ), and 5,5‘‘‘-bis[ N , N -bis(trimethylsilyl)aminomethyl]-2,2‘:5‘,2‘‘:5‘‘,2‘‘‘-quaterthiophene ( 3 ); see Figure for the chemical structure. Although these compounds have been originally obtained as intermediates for aminoalkyl-terminated oligothiophenes, , the intermediates turned out to be quite stable in the absence of acids. In such an environment the materials crystallize in needles or plates of high quality and can be even vacuum-processed into thin films without causing chemical degradation or alteration .…”