We report that ruthenium polypyridyl complexes can catalyze ammonia oxidation to dinitrogen at room temperature and ambient pressure. During bulk electrolysis experiments, gas chromatography and mass spectrometry analysis of the headspace in the electrochemical cell showed that dinitrogen and dihydrogen are generated from ammonia with high faradaic efficiencies. A proposed mechanism where a hydrazine complex is the initial N–N bonded intermediate is supported by chemical and electrochemical experiments. This is a well-defined system for homogeneous electrocatalytic ammonia oxidation. It establishes a platform for answering mechanistic questions relevant to using ammonia to store and distribute renewable energy.

By modifying ligand steric and electronic profiles it is possible to C–H borylate ortho or meta to substituents in aromatic and heteroaromatic compounds, where steric differences between accessible C–H sites are small. Dramatic effects on selectivities between reactions using B2pin2 or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (HBpin) are described for the first time. Judicious ligand and borane combinations give highly regioselective C–H borylations on substrates where typical borylation protocols afford poor selectivities.

Para C–H borylations (CHB) of tetraalkylammonium sulfates and sulfamates have been achieved using bipyridine-ligated Ir boryl catalysts. Selectivities can be modulated by both the length of the alkyl groups in the tetraalkylammonium cations and the substituents on the bipyridine ligands. Ion pairing, where the alkyl groups of the cation shield the meta C–H bonds in the counteranions, is proposed to account for para selectivity. The 4,4′-dimethoxy-2,2′-bipyridine ligand gave superior selectivities.

Ir-catalyzed deborylation can be used to selectively deuterate aromatic and heteroaromatic substrates. Combined with the selectivities of Ir-catalyzed C–H borylations, uniquely labeled compounds can be prepared. In addition, diborylation/deborylation reactions provide monoborylated regioisomers that complement those prepared by C–H borylation. Comparisons between Ir-catalyzed deborylations and Pd-catalyzed deborylations of diborylated indoles described by Movassaghi are made. The Ir-catalyzed process is more effective for deborylating aromatics and is generally more effective in the monodeborylation of diborylated thiophenes. These processes can be applied to complex molecules such as clopidogrel.