Non-resonant enhancement of spontaneous emission of HITC dye in metal-insulator-metal waveguides
More Like this
-
The rational development of catalytic reactions involving cooperative behavior between two catalytic reactive sites represents a frontier area of research from which novel reactivity and selectivity patterns emerge. Within this context, this Feature highlights the development of a cooperative system involving transition metal Lewis acid/base pairs. Bimetallic systems consisting of copper carbene Lewis acids and metal carbonyl anion Lewis bases, (NHC)Cu–[M CO ], are easily synthesized from readily available organometallic building blocks (NHC = N-heterocyclic carbene; [M CO ] − = metal carbonyl anion, e.g. [FeCp(CO) 2 ] − , [Mn(CO) 5 ] − , etc. ). Stoichiometric reactivity studies indicate that the dative Cu←M bonds in these systems are labile towards heterolysis under mild conditions, thus providing in situ access both to polar metal–metal bonds and to “frustrated” transition metal Lewis acid/base pairs as dictated by reaction conditions. Catalytic transformations ranging from C–C and C–B coupling reactions to hydrogenation and other reductions have been developed from both manifolds: bimetallic catalysis involving (a) binuclear intermediates engaging in cooperative bond activation and formation, and (b) orthogonal mononuclear intermediates that operate in either tandem or co-dependent manners. Preliminary indications point to the future emergence of novel reactivity and selectivity patterns as thesemore »