Borylation directed borylation of N-alkyl anilines using iodine activated pyrazaboles.

ABSTRACT: Doubly electrophilic pyrazabole derivatives (pyrazabole = [H2B(μ-C3N2H3)]2) combined with one equiv. of base effect the ortho-borylation of N-alkyl anilines. Initial studies found that the bis(trifluoromethane)sulfonimide ([NTf2]-) pyrazabole derivative, [H(NTf2)B(μ-C3N2H3)]2, is highly effective for ortho-borylation, with this process proceeding through N-H borylation and then ortho C-H borylation. The activation of pyrazabole by I2 was developed as a cheaper and simpler alternative to using HNTf2 as the activator. The addition of I2 forms mono or ditopic pyrazabole electrophiles dependent on stoichiometry. The ditopic electrophile [H(I)B(μ-C3N2H3)]2 was also effective for the ortho-borylation of N-alkyl-anilines, with the primary C-H borylation products readily transformed into pinacol b

SUBMITTER: Millet CRP 

PROVIDER: S-EPMC10631245 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature