Borrowing Hydrogen Amination Reactions: A Complex Analysis of Trends and Correlations of the Various Reaction Parameters

Borrowing hydrogen or the hydrogen autotransfer amination is a powerful approach to create single C-N bonds starting from stable and readily available substrates: amines and alcohols. It is considered as one of the most atom-efficient and green methods to synthesize complex amines. Herein, we attempted to arrange the array of the existing data in a comprehensive and structured manner and determine correlations between the experimental conditions and catalysis outcome both within different groups of cata-lysts and between the defined groups using the machine analysis. For each type of N-nucleophiles (aromatic, aliphatic, and heteroar-omatic amines, amides) the most efficient working conditions were suggested including attributing the optimal base and temperature regime for each metal

Ruthenium catalyst with a planar-chiral arene ligand: synthesis, separation of enantiomers, and application in C-H activation of N-methoxy-benzamides

Heating tert-butyl-tetraline with [(p-cymene)RuCl2]2 produces the racemic complex [(arene)RuCl2]2, which can be separated into enantiomers by chromatography of its diastereomeric adducts with chiral phosphine ligand. The resolved chiral complex catalyzes C-H activation of N-methoxy-benzamides and their annulation with N-vinyl-pivaloyl amide giving dihydroisoquinolones in 50-90% yields and 70:30-90:10 enantiomeric ratio

Synthesis of chiral boranes via asymmetric insertion of carbenes into B-H bonds catalyzed by the rhodium(I) diene complex

Asymmetric insertion of arydiazoacetates into B-H bonds of NHC-BH2R adducts gives rare compounds with chiral boron centers. The reaction is catalyzed by the rhodium(I) complex with the chiral diene ligand tBu2-TFB, which can be conveniently synthesized by diastereoselective coordination of the racemic diene with (S-Salox)Rh(CO)2. The target boranes were obtained typically in 75−90% yields with 90-95% ee and 2:1-5:1 dr

Rhodium-catalyzed insertion of nitrenes into B–H bonds

The paper presents a new method for the formation of B-N bond by the catalytic insertion of nitrenes into organic boranes. The reaction proceeds most selectively for cyclic boranes with 2-phenylpyridine framework and nitrenes generated in situ by oxidation sulfonamides and sulfamates. The most effective catalysts for the process are rhodium and ruthenium carboxylates of [M2(OOCR)4]X type. Complexes with NTTL ligands derived from S-tert-leucine provide chiral products with stereogenic boron atoms. The developed approach can be useful for the introduction of boron heterocycles into functional materials and biologically active molecules