Multiple resonance thermally activated delayed fluorescence enhanced by halogen atoms

Abstract

We synthesised halogen-substituted multiple-resonance (MR) thermally activated delayed fluorescence emitters, namely 2,12-dichloro-N,N,5,9-tetrakis(4-chlorophenyl)-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracen-7-amine (Cl-MR) and 2,12-dibromo-N,N,5,9-tetrakis(4-bromophenyl)-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracen-7-amine (Br-MR). Cl-MR and Br-MR exhibited a decreased delayed fluorescence lifetime and an enhanced reverse intersystem...

High‐Performance Multi‐Resonance Thermally Activated Delayed Fluorescence Emitters for Narrowband Organic Light‐Emitting Diodes

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“…of BBr 3 in o -dichlorobenzene at 200 °C, which afforded mono-borylated compounds Cl-MR and Br-MR in yields of 56% and 63%, respectively. 233 In the synthesis of DBT-BN , DBF-DBN , and DBT-DBN by Wu and Lan et al , the chlorine atoms in the borylation precursor were partially exchanged for bromine during one-shot borylation with BBr 3 . However, this did not present a problem, as these halogen atoms were consumed in the subsequent Suzuki–Miyaura coupling.…”

Elevating the upconversion performance of a multiple resonance thermally activated delayed fluorescence emitter via an embedded azepine approach

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