Site Selective Boron Directed Benzylation of -Aryl Amides: Access to Structurally Diversified Dibenzoazepines.

We present a highly selective protocol for the benzylation of -aryl amides. This method offers mild conditions, excellent site specificity, and scalability, enabling the synthesis of diarylmethane amides and dibenzoazepines. The protocol allows for one-pot diagonal dibenzylation of dianilides, creating valuable precursors for pharmaceutically active compounds and addressing limitations in current direct C-H activation methodologies.

Ortho Arylation of N-Aryl Amides and the Construction of Diagonal Tetraarylbenzenediamines and N-Doped Fulminenes via BBr-Derived Dibromoboracycles.

The synthesis of biaryl amides, which are prevalent motifs in bioactive molecules, often necessitates lengthy and inefficient procedures. To address these limitations, catalytic C-H activation protocols have emerged, enabling the direct ortho-arylation of aryl amides. However, these protocols often suffer from issues such as lack of selectivity, reliance on stoichiometric oxidants, and the requirement for excess reagents and harsh reaction conditions.

Regioselective halogenation of -aryl amides and ureas oxidative halodeboronation: harnessing boron reactivity for efficient C-halogen bond installation.

The installation of the C-halogen bond at the position of -aryl amides and ureas represents a tool to prepare motifs that are ubiquitous in biologically active compounds. To construct such prevalent bonds, most methods require the use of precious metals and a multistep process. Here we report a novel protocol for the long-standing challenge of regioselective halogenation of -aryl amides and ureas using an oxidative halodeboronation.

Boron-Mediated Regioselective Aromatic C-H Functionalization via an Aryl BF Complex.

An efficient regioselective functionalization of 2-aryl-heteroarenes and aryl aldehydes via an azaaryl BF complex has been developed. Mechanistically the reaction comprises fluoride to bromide ligand exchange on an aryl boron species and consecutive C-B bond cleavage to deliver a broad range of functionalized products. The reaction is high yielding, has a broad substrate scope where several different heteroarenes can be functionalized with chloro, bromo, iodo, hydroxyl, amine and BF in a highly regioselective fashion.

Oxone promoted dehydrogenative Povarov cyclization of -aryl glycine derivatives: an approach towards quinoline fused lactones and lactams.

Oxone promoted intramolecular dehydrogenative imino Diels-Alder reaction (Povarov cyclization) of alkyne tethered -aryl glycine esters and amides has been explored, thus affording biologically significant quinoline fused lactones and lactams. The reaction is simple, scalable, and high yielding (up to 88%). The method was further extended to prepare biologically important luotonin-A analogues and the quinoline core of uncialamycin.

Accessing α-Arylated Nitriles via BF·OEt Catalyzed Cyanation of para-Quinone Methides Using tert-Butyl Isocyanide as a Cyanide Source.

BF·OEt catalyzed 1,6-conjugate addition of tert-butyl isocyanide to para-quinone methides and fuchsones for the synthesis of α-diaryl and α-triaryl nitriles has been reported. This protocol allows α-diaryl- and α-triaryl nitriles to be accessed in good to excellent yields and with a broad substrate scope, which could be further functionalized to give a versatile set of products. This is the first example wherein tert-butyl isocyanide has been used as a cyanide source for the 1,6-conjugate addition.