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The ortho-selective benzylic C(sp3)–H alkenylation of 2-methyl tertiary anilines with internal alkynes has been achieved for the first time by using a half-sandwich scandium catalyst. This protocol provides a straightforward route for the synthesis of a new family of 2-allylaniline derivatives, featuring broad substrate scope, 100% atom-efficiency, high yields, and high chemo-, regio-, and stereoselectivity. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, structure, and photophysical and electrophosphorescence properties of heteroleptic amidinate/bis(pyridylphenyl) iridium(iii) complexes having different substituents on the nitrogen atoms of the amidinate ancillary ligands. The reaction of bis(pyridylphenyl) iridium(iii) chloride [(ppy)2Ir(μ-Cl)]2 with the lithium salt of various amidinate ligands Li{(NR)(NR′)CPh} at 80 °C gave in 60–80% yields the corresponding heteroleptic bis(pyridylphenyl)/amidinate iridium(iii) complexes having a general formula [(ppy)2Ir{(NR)(NR′)CPh}], where R = R′ = iPr (1), R = R′ = t-Bu (2), R = Et, R′ = t-Bu (3), and R = Et, R′ = (CH2)3N(CH3)2 (4). These heteroleptic iridium(iii) complexes exhibited bright yellowish-green phosphorescence emission with moderate photoluminescence (PL) quantum yields (ΦPL = 0.16–0.34) and short phosphorescence lifetimes of 0.98–1.18 μs in toluene solution at room temperature. Organic light-emitting diodes (OLEDs) were fabricated by the use of these complexes as phosphorescent dopants in various concentrations (x = 5–100 wt%) in the 4,4′-N,N′-dicarbazolylbiphenyl (CBP) host. Because of the steric hindrance of the amidinate ligands, no significant intermolecular interaction was observed in these complexes, thus leading to the reduction of self-quenching and triple–triplet annihilation at high currents/luminance. A significant influence of the substituents in the amidinate ligands on the electroluminescence efficiency was observed. Among these complexes, complex (2), which contains the bulky t-butyl group on the amidinate nitrogen atoms, showed the highest current efficiency (ηc: up to 116 cd A−1), power efficiency (ηp: up to 72.2 lm W−1) and external quantum efficiency (ηext; up to 16.3%). [ABSTRACT FROM AUTHOR]

The living isospecific-cis-1,4-polymerization and block-copolymerization of (E)-1,3-pentadiene with 1,3-butadiene have been achieved for the first time by using cationic half-sandwich scandium catalysts. [ABSTRACT FROM AUTHOR]

The ortho -selective benzylic C(sp 3 )-H alkenylation of 2-methyl tertiary anilines with internal alkynes has been achieved for the first time by using a half-sandwich scandium catalyst. This protocol provides a straightforward route for the synthesis of a new family of 2-allylaniline derivatives, featuring broad substrate scope, 100% atom-efficiency, high yields, and high chemo-, regio-, and stereoselectivity.

A boryl scandium complex supported by the silylene-linked cyclopentadienyl-amido ligand was synthesized for the first time, which on reaction with nitric oxide (NO) afforded a novel scandium boryldiazeniumdiolate [ON(boryl)NO] complex.

The living isospecific-cis-1,4-polymerization and block-copolymerization of (E)-1,3-pentadiene with 1,3-butadiene have been achieved for the first time by using cationic half-sandwich scandium catalysts.

A neutral 2,2'-dipyridylamido (dpa)-supported bis(cyclometalated) iridium(III) complex [Ir(ppy)(2)(dpa)] (ppy = o-(2-pyridyl)phenyl) has been synthesized and structurally characterized for the first time, which emits green electroluminescence with high current efficiency (123.5 cd A(-1)) and high power efficiency (43.2 lm W(-1))., (© The Royal Society of Chemistry 2011)

The cationic rare earth metal aminobenzyl complexes bearing mono(pyrrolyl) ligands are synthesised and structurally characterised, and the coordination mode of the pyrrolyl ligands is found to show significant influence on the polymerisation of styrene.

A structurally well-defined THF-free cationic half-sandwich scandium aminobenzyl complex serves as a novel catalyst for the first copolymerization of 1-hexene with dicyclopentadiene to give the random copolymers with a wide range of 1-hexene contents (32-70 mol%) unavailable previously.

Organo alkali metal compounds such as (n)BuLi and (Me3Si)2NK act as excellent catalyst precursors for the addition of phosphine P-H bonds to carbodiimides, offering a general and atom-economical route to substituted phosphaguanidines, with excellent tolerability to aromatic C-Br and C-Cl bonds.