A palladium-catalyzed one-pot procedure for the synthesis of aryl ketones has been developed. Triazine esters when coupled with aryl boronic acids provided aryl ketones in moderate to excellent yields (up to 95%) in the presence of 1 mol % Pd(PPh3)2Cl2 for 30 min.

The first examples of benzoborole rare-earth ate complexes [BoRE­(COT)]­[Li­(DME)3] (3RE; Bo = benzoborole dianion; COT = cyclooctatetraene; RE = Y, Dy, Er; DME = 1,2-dimethoxyethane) with a sandwich structure have been synthesized by the reaction of a benzoborole dianion with RECl3 followed by treatment with cyclooctatetraene dipotassium salt. These complexes have been fully characterized by X-ray diffraction analysis and IR, UV–vis, and NMR spectroscopy. Remarkably, the Dy and Er complexes exhibit single-molecule-magnet behaviors with effective energy barriers (U eff) of 98 cm–1 (141 K) and 109 cm–1 (157 K), respectively, and their magnetic hysteresis loops were observed at 2 K.

The synthesis of benzoborole dianions by alkali metal reduction of BN‐naphthalene derivatives via a ring‐contraction strategy has been developed. Reduction of 1‐alkynyl 2,1‐benzazaborine 1 a in Et2O led to the elimination of alkynyllithium with the formation of 1‐amino‐1‐benzoborole trilithium salt 2 a, whereas reduction of 1‐phenyl 2,1‐benzazaborine 1 c in THF yielded 1‐phenyl‐1‐benzoborole dilithium salt 2 c with the elimination of ArNHLi. The trilithium and dilithium salts 2 a and 2 c have been fully characterized. Treatment of trilithium salt 2 a with Et3NHCl led to the selective protonation of the amino lithium to afford the dilithium salt 2 aH, which could be cleanly oxidized to 1‐amino‐1‐benzoborole 3 in an excellent yield. Reaction of 1‐phenyl‐1‐benzoborole dilithium salt 2 c with MeI yielded the lithium borate 4 c, which is luminescent both in solution and in the solid state.

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