Low‐Band Gap Polyplatinaynes with Electron‐Accepting Silole Units

Abstract

Summary: The synthesis and thermal, redox and photoluminescence properties of a soluble donor‐acceptor polyplatinayne with the electron‐accepting silole ring and its model compound are described. The polymer has an optical band gap of 2.10 eV which is much lower than that of thienyl‐ or silyl‐bridged congeners. The incorporation of electron‐accepting silole unit in the metallopolymer main chain creates a new π‐conjugated system that features unique donor‐acceptor characteristics.

Silole‐Containing Polymers: Chemistry and Optoelectronic Properties

“…2,5-Diethynylsilole-based platinayne polymer 76 was prepared by Wong et al (Scheme 33). [108] The M w of 76 reached 17 530 with an M w =M n of 1.77. Polymer 76 showed a T g of 228 8C and a decomposition temperature of 348 8C.…”

“…2,5‐Diethynylsilole‐based platinayne polymer 76 was prepared by Wong et al (Scheme ) 108. The $\overline M _{\rm w}$ of 76 reached 17 530 with an $\overline M _{\rm w} /\overline M _{\rm n}$ of 1.77.…”

Organometallic Polymer Light‐Emitting Diodes Derived from a Platinum(II) Polyyne Containing the Bithiazole Ring

“…[8] While much effort has been devoted to spacers (Ar) like anthracene, carbazole, fluorene, oligothiophene, etc for the tuning of the S 1 and T 1 states (and hence E g ) in polymetallaynes, [8,9] most of these conjugated platinum(II) polyynes are very often characterized by rather large E g , which compare unfavorably with those of their organic competitors comprising alternating electron donor and acceptor units. [6,7] It was not until recently that low-bandgap platinum(II) polyyne polymers with the electron-deficient thieno [3,4-b]pyrazine, [10] dicyanomethylenefluorene, [11] silole [12] thienyl-heteroaryl hybrids [4h-4j] or dicyanomethyleneacridone [13] were prepared using such a D-A concept. It is known that the addition of electron-withdrawing imine nitrogen to a conjugated polymer backbone generally enhances its electron-accepting properties.…”

Electron‐Deficient Acridone Derivatives as a New Functional Core Towards Low‐Bandgap Metallopolyynes

“…for the tuning of the lowest singlet (S 1 ) and triplet (T 1 ) states and energy gaps in polymetallaynes of the type trans-[-Pt(PR 3 ) 2 -C C-R-C C-] n , [6] most of these platinum(II) polyynes are very often characterized by rather large E g , [6] which compare unfavorably with those of their organic competitors comprising alternating electron donor and acceptor units. [1,2] It was not until recently that novel low-bandgap platinum(II) polyyne polymers with the electron-deficient thieno [3,4-b]pyrazine, [3] dicyanomethylenefluorene, [4] or silole unit [5] were prepared using such D-A concept. To the best of our knowledge, however, the acridone chromophore has not been widely used in this area.…”

“…[1] Successful strategies for creating narrow-bandgap polymers involve the construction of donor-acceptor (D-A) type systems. [2][3][4][5] While many endeavors have been made to employ fluorescent spacers R such as anthracene, carbazole, fluorene, oligothiophene, etc. for the tuning of the lowest singlet (S 1 ) and triplet (T 1 ) states and energy gaps in polymetallaynes of the type trans-[-Pt(PR 3 ) 2 -C C-R-C C-] n , [6] most of these platinum(II) polyynes are very often characterized by rather large E g , [6] which compare unfavorably with those of their organic competitors comprising alternating electron donor and acceptor units.…”