Poly(p‐phenyleniminoboran): ein Bor‐Stickstoff‐Analogon von Poly(p‐phenylenvinylen)

Abstract

Der isoelektronische und isostere Austausch ausgewählter CC-durchB N-Einheiten in p-konjugierten organi-schenS ystemen (BN/CC-Isosterie) hat sich als erfolgreiche Strategie zur Entwicklung BN-dotierter polycyclischer aromatischer Kohlenwasserstoffe (PAKs) mit faszinierenden Eigenschaften und Funktionen erwiesen. Unlängst haben erste Beispiele die Nützlichkeit dieses Konzepts in der Polymerchemie gezeigt. Hier stellen wir die Synthese und Charakterisierung des ersten Poly(p-phenyleniminoborans) vor.D ieses neue anorganisch-organische Hybridpolymer kann als BN-Analogon des bekannten Poly(p-phenylenvinylens) (PPV) angesehen werden. Photophysikalische Untersuchungen am Polymer und einer Reihe von Modelloligomeren geben eindeutige Hinweise auf p-Konjugation über die B = N-Bindungen und eine Erweiterung der Konjugationslänge mit wachsender Kettenlänge.T D-DFT-Rechnungen verschaffen einen tieferen Einblicki nd ie elektronische Struktur der neuen Materialien. Schema 1. Repräsentative Beispiele für p-konjugierte organische Polymere und ihre BN-Isostere. Mes = 2,4,6-Trimethylphenyl, Mesityl; Oct = n-C 8 H 17 ;R,R' = organische Substituenten oder H.

Poly(arylene iminoborane)s, Analogues of Poly(arylene vinylene) with a BN‐Doped Backbone: A Comprehensive Study

“…We previously reported the synthesis of poly( p ‐phenylene iminoborane) (BN‐PPV) 22 through silicon/boron exchange co‐polycondensation of 9 and N,N′ ‐bis(trimethylsilyl)‐ p ‐phenylenediamine ( 24 ) [15] . Now, we demonstrate that 22 can also be prepared by polycondensation of 9 with p ‐phenylenediamine ( 16 ) through salt elimination in the presence of NEt 3 (Scheme 4).…”

“…The molecular structures of all compounds feature perfectly trigonal‐planar coordinated boron and nitrogen centers (both ∑(NR 3 ) and ∑(BR 3 )=360.0°). The B−N bond lengths of 5 , 12 , 14 , 18 , and 20 are between 1.396(3)–1.414(2) Å (Table S2), thus, in the same range with those of the BN‐PPV [15] and BN‐PTV [16] model oligomers and related aminoboranes having pronounced double bond character [22] . Furthermore, the phenyl(ene) and thienyl(ene) rings are rotated in a way that they are, to a certain degree, coplanar with the >B=N< moieties they are bound to.…”

“…This isosteric substitution conserves the basic structural features of the parent carbonaceous system, but it usually results in modified, often intriguing electronic and photophysical properties, as well as altered chemical reactivity [6,7] . While this concept has been extensively applied to polyaromatic molecules, [6,7] application of this concept to polymer chemistry has come into the focus of active research only quite recently [8–16] …”

Syntheses and Structures of Transition Metal Complexes with Phosphanylphosphinidene Chalcogenide Ligands

“…19 The sulfurization of the phosphenium complexes [Cp(OC) 2 WP{N(SiMe 3 ) 2 }(Ph)] 20 or [(C 5 R 5 )(OC) 2 WP(H)tBu] 21 leads to the addition of an S atom to the MP bond, while a similar reaction with the Fe(II) phosphido complex [Cp(OC) 2 Fe−PPh 2 ] yields [Cp-(OC) 2 Fe−P(S)Ph 2 ]. 22 The addition of H 2 O to [dppe 2 ReCl(P ≡ CtBu)] gives the complex [dppe 2 ReCl(P(O)−CH 2 tBu)] with a phosphinidene oxide ligand. 23 formation and properties of the anionic complex [(η 5 -C 5 H 5 )(OC) 2 MoP(O)Ar] − (Ar = 2,4,6-tBu 3 C 6 H 2 ).…”

Effects of the Substituents of Boron Atoms on Conjugated Polymers Containing B←N Units

“…N Lewis pair has been employed to modulate molecular orbitals and thereby to tune absorption and fluorescences pectra of conjugated molecules and polymers. [28][29][30][31][32][33][34][35][36][37] Our group has recently discovered that intramolecular B ! NL ewis pair formation can significantly downshift LUMO/HOMO energy levels (E LUMO /E HOMO )o fc onjugated polymers.…”