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A uniquely stable acyl potassium trifluoroborate, potassium (2-phenylacetyl)trifluoroborate, has been synthesized and isolated. In the presence of an activating Lewis acid, this reagent reacts with azides to form amides in good yields.

A number of alkynyl pinacolboronates bearing various functional groups were synthesized according to literature methods. These were then stereoselectively reduced to the cis-alkenyl pinacolboronates via hydroboration with dicyclohexylborane followed by chemoselective protodeboronation using acetic acid. Treatment with potassium hydrogen fluoride smoothly converted these to the corresponding potassium organotrifluoroborates.

Aryl bromides bearing a potassium trifluoroborate moiety were subjected to lithium-halogen exchange at low temperature using a variety of alkyllithium reagents. A number of different electrophiles were evaluated in their reactions with the aryllithiums produced therein. Under carefully optimized conditions, potassium bromophenyl trifluoroborates afforded good to excellent yields of the corresponding alcohols (64-94% isolated yield) when aldehydes or ketones were used as the electophilic partner. Esters were unfortunately found to be unreactive.

Rational design of supramolecular systems for application in photonic devices requires a clear understanding of both the mechanism of energy and electron transfer processes and how these processes can be manipulated. Central to achieving these goals is a detailed picture of their electronic structure and of the interaction between the constituent components. We review several approaches that have been taken towards gaining such understanding, with particular focus on the physical techniques employed. In the discussion, case studies are introduced to illustrate the key issues under consideration.