SYNLETT Best Paper Award 2018: A Protocol for Direct Stereospecific Amination of Primary, Secondary, and Tertiary Alkylboronic Esters
James Morken highlights his award-winning paper on a protocol for stereospecific amination of alkylboronic esters.
The award-winning article deals with the direct stereospecific amination of primary, secondary, and tertiary alkylboronic esters. Over the past decade or so, there has been a tremendous surge in the development of processes, both catalytic and non-catalytic, that result in the enantioselective construction of compounds bearing boronic ester functional groups attached to stereogenic carbon atoms. While these reaction products may be oxidized to give chiral alcohols, or subjected to C–C bond-forming homologation reactions, a simple and effective amination of boronic esters in a stereospecific fashion really wasn’t available. A few years ago, the group of Professor James Morken developed one protocol for accomplishing this objective, but it required the use of pyrophoric reagents and very low reaction temperatures, and was ineffective with some substrate classes, most notably tertiary alkylboronic esters. The paper selected for the SYNLETT Best Paper Award fixed all of these problems: it uses a simple base, can be conducted in the open atmosphere, and applies to primary, secondary, and tertiary alkylboronic esters. With this strategy, it is now just as easy to convert an alkylboronic ester into an amine as it is into an alcohol.