Oxidation-induced nucleophilic substitution at the electron-rich B(12) vertex in [CB₁₁H₁₂]^- under catalyst-free conditions.

ABSTRACT: Highly regioselective B(12) substitutions of the monocarborane anion [CB₁₁H₁₂]^- has been a challenge. Here, we synthesized a stable B-O-N zwitterionic compound with an impressive yield (isolated yield up to 98%) and excellent regioselectivity at the B(12) position under catalyst-free conditions. The kinetics, substituent effect, and capture experiments are paired with theoretical calculations, showing that the reaction mechanism is oxidation-induced nucleophilic substitution. The hydride anion at the B(12) position is abstracted by an oxoammonium oxidant with lower cleavage energy of 4.2 kcal mol^-1 than B(7-11) positions, thereby changing the electronegativity upon the conversion of [CB₁₁H₁₂]^- to neutral [CB₁

SUBMITTER: Sun W 

PROVIDER: S-EPMC11884434 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature