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1,4‐BN‐doped polycyclic aromatic hydrocarbons (PAHs) have emerged as very promising emitters in organic light‐emitting diodes (OLEDs) due to their narrowband emission spectra that may find application in high‐definition displays. While considerable research has focused on investigating the properties of these materials, less attention has been placed on their synthetic methodology. Here we developed an efficient synthetic method for 1,4‐BN‐doped PAHs, which enables sustainable production of narrowband organic emitting materials. By strategically introducing substituents, such as methyl, tert‐butyl, phenyl, and chloride, at the C5 position of the 1,3‐benzenediamine substrates, we achieved remarkable regioselective borylation in the para‐position of the substituted moiety. This approach facilitated the synthesis of a diverse range of 1,4‐BN‐doped PAHs emitters with good yields and exceptional regioselectivity. The synthetic method demonstrated excellent scalability for large‐scale production and enabled late‐stage transformation of the borylated products. Mechanistic investigations provided valuable insights into the pivotal roles of electron effect and steric hindrance effect in achieving highly efficient regioselective borylation. Moreover, the outstanding device performance of the synthesized compounds 10 b and 6 z, underscores the practicality and significance of the developed method. [ABSTRACT FROM AUTHOR]

Reported herein is a chemical method for the direct resolution of unprotected racemic β-substituted-β-amino acids (β³-AAs) that uses specially designed, stable, and recyclable α- methylproline-derived chiral ligands. The versatility of this methodology is unmatched by biocatalytic approaches. The method shows a broad synthetic generality for various aryl- or alkyl-substituted β³-AAs, and the new nonracemizable ligands can be accessed readily. Furthermore, the presented method produces an excellent stereochemical outcome and has a fully recyclable source of chirality, and the reaction conditions are operationally simple and convenient. The procedure has also been successfully applied to the scalable synthesis of the anti- HIV drug maraviroc. [ABSTRACT FROM AUTHOR]

Structurally simple and inexpensive chiral tridentate ligands were employed for substantially advancing the purely chemical dynamic kinetic resolution (DKR) of unprotected racemic tailor-made α-amino acids (TM-α-AAs), enabling the first DKR of TM-α-AAs bearing tertiary alkyl chains as well as multiple unprotected functional groups. Owing to the operationally convenient conditions, virtually complete stereoselectivity, and full recyclability of the source of chirality, this method should find wide applications for the preparation of TM-α-AAs, especially on large scale. [ABSTRACT FROM AUTHOR]

Reported herein is the first purely chemical method for the dynamic kinetic resolution (DKR) of unprotected racemic α-amino acids (α-AAs), a method which can rival the economic efficiency of the enzymatic reactions. The DKR reaction principle can be readily applied for S/R interconversions of α-AAs, the methodological versatility of which is unmatched by biocatalytic approaches. The presented process features a virtually complete stereochemical outcome, fully recyclable source of chirality, and operationally simple and convenient reaction conditions, thus allowing its ready scalability. A quite unique and novel mode of the thermodynamic control over the stereochemical outcome, including an exciting interplay between axial, helical, and central elements of chirality is proposed. [ABSTRACT FROM AUTHOR]

The purely chemical dynamic kinetic resolution of α‐amino acids bearing tertiary alkyl chains and multiple unprotected functional groups is based on the enantioselective formation of nickel(II) complexes and their disassembly under convenient conditions. In their Communication on page 12918 ff., H. Liu, V. A. Soloshonok et al. show that the specially designed chiral ligands can be easily recycled while the target amino acids are isolated in good yields and excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Die rein chemische dynamische kinetische Racematspaltung von α ‐ Aminosäuren mit tertiären Alkylketten und unterschiedlichsten funktionellen Gruppen basiert auf der enantioselektiven Bildung eines Nickel(II) ‐ Komplexes und dessen Hydrolyse. In der Zuschrift auf S. 13110 ff. zeigen H. Liu, V. A. Soloshonok et al., dass die hierfür entwickelten Liganden leicht wiederverwendet werden können, während die gewünschten Aminosäuren in guten Ausbeuten und mit exzellenter Enantioselektivität isoliert wurden. [ABSTRACT FROM AUTHOR]