A Cheap and Efficient Oxidant (n-Bu)4NNO3-Enabled C(sp2)- and C(sp3)-H Olefination at Room Temperature.

To further promote the widely practical application of C-H activation, developing green and mild reaction conditions has invariably been the objective of researchers, especially when it comes to remote C-H activation reactions. Herein, we report a new cheap and powerful (n-Bu)4NNO3 oxidant. This oxidant is efficient and universal for Pd(II)-catalyzed sp2 and sp3 C-H olefination and allows the reaction to be carried out at room temperature. Because of this, we attempted to make C-H functionalization more economical and environmentally benign.

Cobalt(III)-catalyzed weakly coordinating arylurea-directed regioselective mono-olefination.

Here, we developed an air-stable, earth-abundant cobalt(III)-catalyzed regioselective mono-olefination of arenes directed by urea under mild conditions through a cross-dehydrogenative coupling (CDC) process. Under the optimized conditions, a high regioselectivity of mono-olefination was achieved with various electron-rich and electron-deficient arenes, which afforded E-alkenylated products (with yields of up to 90%). In contrast to the conditions used for noble-metal-catalyzed olefination directed by weakly coordinating groups, our reaction was operated under mild conditions, including mild temperature (40 °C) and non-metallic oxidant.

(Acetyl-acetonato-κO,O')bis-[2-(5-methyl-3-phenyl-pyrazin-2-yl-κN)phen-yl-κC]iridium(III).

In the title complex, [Ir(C(17)H(13)N(2))(2)(C(5)H(7)O(2))], the Ir(III) atom is hexa-coordinated in a distorted octa-hedral geometry by two C,N-bidentate 2-(5-methyl-3-phenyl-pyrazin-2-yl)phenyl (mdpp) ligands and one O,O-bidentate acetyl-acetonate ligand. The dihedral angles between the phenyl rings and the pyrazine ring are 9.56 (14) and 58.99 (14)° for one mdpp ligand and 9.34 (14) and 79.94 (15)° for the other.