Efficient and selective carbonyl hydroboration catalyzed by a lithium NCN-Pincer magnesiate complex [Li(THF)(4)][NCN-MgBr2]

The well-defined lithium NCN-Pincer magnesiate complex [Li (THF)(4)][NCN-MgBr2](2) based on a bis(i-mino)aryl ligand has been successfully prepared, crystallographic characterized and employed as an efficient catalyst for hydroboration of a wide range of aldehydes and ketones with pinacolborane (HBpin) at room temperature. Both aldehyde and ketone hydroboration proceeded efficiently (>99% conversion in <15 min) and could be directly carried out in a CDCl (3) solution. In addition, chemoselective hydroboration of aldehydes over ketones was also achieved under these conditions. (C) 2018 Elsevier B.V. All rights reserved.