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Imine as a linchpin approach for meta-C-H functionalization.

ABSTRACT: Despite the widespread applications of C-H functionalization, controlling site selectivity remains a significant challenge. Covalently attached directing groups (DGs) served as ancillary ligands to ensure ortho-, meta- and para-C-H functionalization over the last two decades. These covalently linked DGs necessitate two extra steps for a single C-H functionalization: introduction of DG prior to C-H activation and removal of DG post-functionalization. Here we report a temporary directing group (TDG) for meta-C-H functionalization via reversible imine formation. By overruling facile ortho-C-H bond activation by imine-N atom, a suitably designed pyrimidine-based TDG successfully delivered selective meta-C-C bond formation. Application of this temporary directing group strategy for streamlining the synthesis of complex organic molecules without any necessary pre-functionalization at the meta position has been explored.

SUBMITTER: Bag S

PROVIDER: S-EPMC7925593 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Imine as a linchpin approach for meta-C-H functionalization.

Bag Sukdev S Jana Sadhan S Pradhan Sukumar S Bhowmick Suman S Goswami Nupur N Sinha Soumya Kumar SK Maiti Debabrata D

Nature communications 20210302 1

Despite the widespread applications of C-H functionalization, controlling site selectivity remains a significant challenge. Covalently attached directing groups (DGs) served as ancillary ligands to ensure ortho-, meta- and para-C-H functionalization over the last two decades. These covalently linked DGs necessitate two extra steps for a single C-H functionalization: introduction of DG prior to C-H activation and removal of DG post-functionalization. Here we report a temporary directing group (TD ...[more]

PMID: 33654108

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