Achieving High Ortho Selectivity in Aniline C-H Borylations by Modifying Boron Substituents.

ABSTRACT: High ortho selectivity for Ir-catalyzed C-H borylations (CHBs) of anilines results when B₂eg₂ (eg = ethylene glycolate) is used as the borylating reagent in lieu of B₂pin₂, which is known to give isomeric mixtures with anilines lacking a blocking group at the 4-position. With this modification, high selectivities and good yields are now possible for various anilines, including those with groups at the 2- and 3-positions. Experiments indicate that ArylN(H)Beg species are generated prior to CHB and support the improved ortho selectivity relative to B₂pin₂ reactions arising from smaller Beg ligands on the Ir catalyst. The lowest-energy transition states (TSs) from density functional theory computational analyses have N-H···O hy

SUBMITTER: Smith MR 

PROVIDER: S-EPMC6105271 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature