Dual for a transfer! A strategy has been devised for functionalizing fluorescent diketopyrrolopyrroles (DPP) dyes with a borondipyromethene (BODIPY) unit acting as an energy acceptor (see scheme). Quantitative intramolecular electronic energy transfer is effective by excitation in the DPP subunit in apolar and polar media, including aqueous methanol, to provide large Stoke shifts.
Dipalladium(I) and diruthenium(I) compounds bridged by two [{(5,7-dimethyl-1,8-naphthyridin-2-yl)amino}carbonyl]ferrocene (L) ligands have been synthesized. The X-ray structures of [Pd2L2][BF4]2 (1) and [Ru2L2(CO)4][BF4]2 (2) reveal dinuclear structures with short metal–metal distances. In both of these structures, naphthyridine bridges the dimetal unit, and the site trans to the metal–metal bond is occupied by weakly coordinating oxygen from the amido fragment. The catalytic utilities of these bimetallic compounds are evaluated. Compound 1 is an excellent catalyst for phosphine-free, Suzuki cross-coupling reactions of aryl bromides with arylboronic acids and provides high yields in short reaction times. Compound 1 is also found to be catalytically active for aryl chlorides, although the corresponding yields are lower. A bimetallic mechanism is proposed, which involves the oxidative addition of aryl bromide across the Pd
Good couple: Metal–metal singly bonded [PdI
