A square-planar Pt(II) complex with a pyridine-based pincer-type N-heterocyclic carbene ligand, [PtII(C∧N∧C)(Cl)]Cl (C∧N∧C = 2,6-bis(1-butylimidazol-2-ylidenyl)pyridine), was synthesized as a new type of emitter and structurally characterized. The complex shows aquachromic photoluminescence in the solid state upon hydration and dehydration.

N-Nitrosation of secondary amines was accomplished in an efficient manner using tert-butyl nitrite under solvent, metal and acid free conditions.

A pyridine-based pincer-type N-heterocyclic carbene complex of Pt(II), [Pt(II)(mesC∧N∧C)CO](PF6)2 (mesC∧N∧C = 2,6-bis(1-mestylimidazol-2-ylidenyl)pyridine), displays size-selective vapochromic behavior upon exposure to small molecules with donor atoms. An acetone adduct showing a weak interaction between acetone and a CO ligand is also structurally determined.

The methylenebis(N-alkylimidazolium) halides are converted to dialkylbiimidazoles by cuprous oxide with concurrent C−N bond cleavage and C−C bond formation. This unusual C−N bond cleavage is proposed to involve a Cu(I)−NHC (N-heterocyclic carbene) complex. The reaction is unique, as it involves C−H bond activation, C−N bond cleavage, and C−C bond formation.

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A conversion of o-phenylenediamines into benzotriazoles was achieved at room temperature using tert-butyl nitrite. The optimized conditions are also well suited for the transformation of sulfonyl and acyl hydrazines into corresponding azides. This protocol does not require any catalyst or acidic medium. The desired products were obtained in excellent yields in a short span of time.

Conversion of a wide range of N-Boc amides to aryl ketones was achieved with Grignard reagents via chemoselective C(O)−N bond cleavage. The reactions proceeded under catalyst-free conditions with different aryl, alkyl, and alkynyl Grignard reagents. α-Ketoamide was successfully converted to aryl diketones, while α,β-unsaturated amide underwent 1,4-addition followed by C(O)−N bond cleavage to provide diaryl propiophenones. N-Boc amides displayed higher reactivity than Weinreb amides with Grignard reagents. A broad substrate scope, excellent yields, and quick conversion are important features of this methodology.

The copper meditated N-methylation of sulfoximines using methylboronic acid is reported. The reactions provide excellent yields in a short span of time under mild conditions. The optimized conditions were also found to be suitable for the N-alkylation of sulfoximine with different alkylboronic acids. In addition, N-methylation and cyclopropylation of the bioactive l-methionine sulfoximine derivative was demonstrated under standard reaction conditions.