Introducing Perylene as a New Member to the Azaborine Family

Substitutional doping of perylene with two boron atoms at the 6b/12b positions and two oxygen or nitrogen atoms at the 1/7 positions has been achieved. The modular synthesis route developed for these bis‐BO‐ (3) and bis‐BN‐perylenes (5) starts from the readily accessible borinic acid derivative of the doubly brominated 9,10‐dihydro‐9,10‐diboraanthracene (DBA), 1,5‐Br2DBA(OH)2. A Stille‐type reaction first furnishes the alkynyl‐substituted species 1,5‐(RCC)2DBA(OH)2 (2), which undergo double ring closure to afford 3 via the gold‐catalyzed addition of the O−H bonds to the C≡C bonds. Treatment of 2 with MeN(SiMe3)2 leads to aminoborane intermediates 1,5‐(RCC)2DBA(N(H)Me)2, which can be ring‐closed to give 5 in a similar manner as in the case of 3. Different substituents R (such as Me, tBuPh) can be introduced at the 2/8 positions of the perylene core. The products obtained undergo reversible reduction and are efficient blue/turquoise emitters. BN/CC isosterism: Doubly BO‐ and BN‐doped perylenes have been prepared, which further expand the chemical space of a ubiquitous building block for organic electronic materials. The key cyclization step proceeds via a quantitative Wacker‐type addition reaction of BO−H or BN−H bonds to adjacent alkynyl moieties.