RESUMO
The initiation and control of chemical coupling has the potential to offer much within the context of "bottom up" nanofabrication. We report herein the use of a palladium-modified, catalytically active, AFM probe to initiate and spatially control surface-confined Suzuki and Heck carbon-carbon coupling reactions. These "chemically written reactions", detectable by lateral force and chemically specific optical and topographic labeling, were patterned with line widths down to 15 nm or approximately 20 molecules. Catalyzed organometallic coupling was, in this way, carried out at subzeptomolar levels. By varying the catalyst-substrate interaction times, turnover numbers of (0.6-1.2) x 10(4) and (3.0-5.0) x 10(4) molecules s(-1) were resolved for Suzuki and Heck reactions, respectively.
RESUMO
Appropriately modified proximal probes can be utilized in the spatially resolved chemical coupling of surface-bound and solution-phase reagents. Herein we report a chemically specific Suzuki coupling reaction between a surface-confined aryl bromide and boronic acid reagents in solution achieved using a catalytic AFM probe.