Catalytic insertion of nitrenes into B-H bonds.

Organic compounds with boron-nitrogen bonds are widely used as fluorescent sensors and semiconducting materials. This paper presents a new approach for the formation of B-N bonds via catalytic insertion of nitrenes into B-H bonds. The reaction proceeds most selectively for cyclic boranes with a 2-phenylpyridine framework and nitrenes generated in situ by the oxidation of sulfonamides and sulfamates. The most effective catalysts for this process are the readily available rhodium and ruthenium carboxylates of [M2(OOCR)4]X type. Complexes with carboxylate ligands NTTL derived from S-tert-leucine provide unique chiral products with stereogenic boron atoms. The developed method can be used for the introduction of boron heterocycles into biologically active molecules.