Boron difluoride formazanates with thiophene and 3,4-ethylenedioxythiophene capping and their electrochemical polymerization

Abstract

We report here the first example of BF2 formazanates with thiophenes capping and their π-conjugated polymers in the form of electroactive uniform thin films by electrochemical polymerization. These new formazanates...

π-Conjugated Copolymers Composed of Boron Formazanate and Their Application for a Wavelength Converter to Near-Infrared Light

“… These facts suggest that the direct connection between formazanate moieties and comonomers should lead to the even more effective electronic interaction along the polymer chains than the introduction of triazole units. The limited amount of the spectral shifts might be due to the steric hindrance disturbing the planarity of the main chains compared to the reported polymers composed of platinum acetylide or thiophene …”

“…Scheme shows the synthetic outline of the polymers. The dibrominated monomer B-Br was obtained through boron complexation with the corresponding formazanate ligand L-Br with a slightly modified method of the previous reports. , The copolymers pB-FL and pB-BT were synthesized with the Migita–Kosugi–Stille coupling , using distannyl comonomers of bithiophene (BT) and fluorene (FL), respectively. The palladium-catalyzed Suzuki–Miyaura coupling polymerization using 9,9-didodecylfluorene-2,7-diboronic acid and L-Br , on the other hand, afforded the corresponding ligand polymer pL-FL as a red solid.…”

“…In particular, it has been clarified that the introduction of the electron-donating groups into the boron formazanate complex leads to NIR emission as well as red-shifted absorption thanks to the strong electron-accepting nature of boron formazanates. , Thus, π-conjugated polymers based on boron formazanate complexes have attracted growing attention in recent years. There are limited examples of main-chain-type π-conjugated polymers composed of boron formazanates: Huisgen cycloaddition produces 1,2,3-triazole-containing polymers, Pt­(II)-acetylides-containing polymers were obtained with the reaction between the complex consisting of two terminal alkynes and trans -[Pt­(PBu 3 ) 2 Cl 2 ], and electropolymerization of thienyl complexes . However, π-conjugated polymers containing boron formazanates in the main chains have not been synthesized with transition metal catalyzed cross-coupling polymerizations, although Migita–Kosugi–Stille cross-coupling between a dibrominated complex and a stannylthiophene was reported .…”

“…43,44 formazanates: Huisgen cycloaddition produces 1,2,3-triazolecontaining polymers, 45 Pt(II)-acetylides-containing polymers were obtained with the reaction between the complex consisting of two terminal alkynes and trans-[Pt(PBu 3 ) 2 Cl 2 ], 46 and electropolymerization of thienyl complexes. 47 However, πconjugated polymers containing boron formazanates in the main chains have not been synthesized with transition metal catalyzed cross-coupling polymerizations, although Migita− Kosugi−Stille cross-coupling between a dibrominated complex and a stannylthiophene was reported. 47 Therefore, there is still much room for development of the π-conjugated polymers based on boron formazanates.…”

2-(4-(Dimethylamino)phenyl)-3,3-difluoro-4,6-diphenyl-3,4-dihydro-1,2,4,5,3-tetrazaborinin-2-ium-3-ide

“…The purposeful study of boron formazanates was started in 2007 by Gilroy et al [22] Later, efficient synthesis of them was proposed in toluene medium in the presence o triethylamine [23]. Different derivatives based on cyano- [24], nitro- [25] and triarylfor mazans [19,[26][27][28][29] have been obtained.…”