Borane-Mediated Highly Secondary Selective Deoxyfluorination of Alcohols.

Organofluorine compounds are vital across multiple sectors, hence highly selective methods to install fluorine are of considerable importance. The deoxyfluorination of alcohols is a key approach to prepare organofluorine compounds, however, a highly secondary (2°)-selective deoxyfluorination of alcohols has not been realized to date. Herein, we report that borane-mediated deoxyfluorination results in high 2°-selectivity in inter- and intra-molecular competition reactions versus primary (1°), tertiary (3°) and even benzylic (Bn) alcohols.

-Directed Two-Fold Bromoboration of Diynes Enables Access to Brominated BN-Embedded PAHs.

-directed 2-fold bromoboration reactions of diynes with BBr have been developed, allowing the access to novel internally BN-doped polycyclic aromatic hydrocarbons from readily available precursors under mild conditions. Computational investigations identified three potential reaction mechanisms, each involving either BBr or [BBr], with low activation barriers ( < 16 kcal/mol) for all pathways. The resulting brominated products can be further functionalized through various cross-coupling protocols, enabling the synthesis of highly luminescent emitters with quantum yield exceeding 90.

A Base-Free Two-Coordinate Oxoborane.

Oxoboranes (R-BO) are transient species that rapidly trimerise to form boroxines. To date, the only method used to stabilise oxoboranes is to add a Lewis base, but this forms a three-coordinate at boron oxoborane that has a different bonding/reactivity profile. Herein we report a base-free, two-coordinate oxoborane that is isolated as a Lewis adduct with AlCl.

Transition Metal-Free Catalytic C-H Zincation and Alumination.

C-H metalation is the most efficient method to prepare aryl-zinc and -aluminium complexes that are ubiquitous nucleophiles. Virtually all C-H metalation routes to form Al/Zn organometallics require stoichiometric, strong Brønsted bases with no base-catalyzed reactions reported. Herein we present a catalytic in amine/ammonium salt (EtN/[(EtN)H]) C-H metalation process to form aryl-zinc and aryl-aluminium complexes.

Borylation-Reduction-Borylation for the Formation of 1,4-Azaborines.

Given the current interest in materials containing 1,4-azaborine units, the development of new routes to these structures is important. Carbonyl directed electrophilic borylation using BBr is a facile method for the -borylation of ,-diaryl-amide derivatives. Subsequent addition of EtSiH results in carbonyl reduction and then formation of 1,4-azaborines that can be protected using a Grignard reagent.