Indolocarbazole-Based Ligands for Ladder-Type Four-Coordinate Boron Complexes

Abstract

A novel class of π-conjugated systems, which combine the indolo[3,2-b]carbazole unit with the formation of four-coordinate boron complexes, is presented. The resulting conjugated compounds have a double-laddered structure that provides interesting optical and electrochemical properties. The wide absorption range, covering most of the visible spectrum, along with the narrowing of the HOMO-LUMO energy gap, due to the presence of diphenylboryl centers, reinforces the potential of these molecules within the area of organic electronics.

Near‐IR Absorbing Ruthenium Complexes of Non‐Innocent 6,12‐Di(pyridin‐2‐yl)indolo[3,2‐b]carbazole: Variation as a Function of Co‐Ligands

“…The molecular identities of the representative dimeric [1]ClO 4 (DD/LL, rac), [4](ClO 4 ) 2 (DL, meso), and monomeric [3]ClO 4 (L), [5]ClO 4 (L)c omplexes were authenticated by their single-crystal X-ray structures ( Figure 2, Table 1a nd Ta bles S1-S8 in the SupportingI nformation). Thed eviation of cis and trans angles around the metal ions in the crystals of [1]ClO 4 , [3]ClO 4 ,[ 4](ClO 4 ) 2 ,a nd [5]ClO 4 from the idealized 908 and 1808, respectively,r evealed ad istortedo ctahedral arrangement in each case.…”

“…Shorter Ru III ÀN(pyridine/indole)b ondl engths in [1]ClO 4 (2.047 /1.963 )w ith respect to those in [3]ClO 4 (2.108 / 2.096 ), [4](ClO 4 ) 2 (2.120 /2.069 ), or [5]ClO 4 (2.106 / 2.073 )could be attributedtot he impact of Ru III in the former versus Ru II in the latter.…”

“…[3] Insertion of electron-deficient pyridine groups at the selective 6,12 positions of the indolo [3,2b]carbazole backbone, that is, H 2 L, introduces the concurrence of ap ush-pullm otif and also facilitates its function as ab is-bidentate bridge between the two metal units on deprotonation. [3] Coordinationt ot he metal ion in general lowerst he HOMO-LUMO gap of the molecule and thus may impart electronic absorptionb and(s) well into the NIR domain with increasing transition dipole moment. [3] Coordinationt ot he metal ion in general lowerst he HOMO-LUMO gap of the molecule and thus may impart electronic absorptionb and(s) well into the NIR domain with increasing transition dipole moment.…”

Diboron complexes with bis-spiro structures as high-performance blue emitters for OLEDs

“…PBPOH (572 mg, 2 mmol) was dissolved in dry THF (40 mL) to obtain a clear solution, and then DBA(Br) 2 (332 mg, 1 mmol) was added to the solution. Found: C,80.75;H,4.52;N,7.61. The residue was purified by vacuum sublimation to afford complex 1 as a light green solid (558 mg, 75%).…”

“…Calcd (%) for C 34 H 24 B 2 N 2 O 2 : C,79.42;H,4.70;N,5.45. PPOH (342 mg, 2 mmol) was dissolved in dry THF (40 mL) to obtain a clear solution, and then DBA(Br) 2 (332 mg, 1 mmol) was added to the solution.…”