Steric Shielding Effects Induced by Intramolecular C-H⋯O Hydrogen Bonding: Remote Borylation Directed by Bpin Groups.

ABSTRACT: Regioselectivities in catalytic C-H borylations (CHBs) have been rationalized using simplistic steric models and correlations with nuclear magnetic resonance (NMR) chemical shifts. However, regioselectivity can be significant for important substrate classes where none would be expected from these arguments. In this study, intramolecular hydrogen bonding (IMHB) can lead to steric shielding effects that can direct Ir-catalyzed CHB regiochemistry. Bpin (Bpin = pinacol boronic ester)/arene IMHB can promote remote borylations of N-borylated anilines, 2-amino-N-alkylpyridine, tetrahydroquinolines, indoles, and 1-borylated naphthalenes. Experimental and computational studies support molecular geometries with the Bpin orientation controlled by a C-H⋯O IMHB. IMHB-directed remote CHB appeared operat

SUBMITTER: Bastidas JRM 

PROVIDER: S-EPMC9854017 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature