para-Selective C–H bond functionalization of iodobenzenes

Abstract

Selective C-H bond activation and functionalization is an invaluable and eco-friendly tool for new chemical bond construction. Recently, great progress has been made in the highly selective ortho- and meta-C-H bond functionalization of arene derivatives. In contrast, the remote para-C-H bond functionalization still remains a challenge. Herein, an oxidation-induced strategy for para-selective C-H bond functionalization of iodobenzenes towards the synthesis of various useful asymmetric diaryl ethers was demonstrated. This strategy not only provides a novel method for para-C-H bond functionalization, but also proposes a general idea for the development of new, highly selective para-C-H functionalization reactions.

Copper-Catalyzed Remote C–H Functionalizations of Naphthylamides through a Coordinating Activation Strategy and Single-Electron-Transfer (SET) Mechanism

“…Classical synthetic methods used to achieve p -C Ar –H site selectivity are based on electrophilic aromatic substitution but typically require harsh conditions and afford a mixture of ortho/para isomers in parallel. Therefore, the exploration of a novel and general synthetic methodology for the highly selective p -C–H functionalization is still highly desirable. , Herein, we demonstrate a radical aromatic substitution strategy for para-selective C–H functionalization of 1-naphthylamides in this work.…”

One-pot two-step synthesis of 3-iodo-4-aryloxy coumarins and their Pd/C-catalyzed annulation to coumestans

“…Towards the mechanistic insight, we speculated that m CPBA could oxidize the iodobenzene to iodosobenzene (PhIO, A), which might be one of the key intermediates 14 a , b ( Scheme 2 ). According to the previous report of Lei et al , 15 iodosobenzene could react with pivalic acid to form B, which further gives rise to phenyl iododipivalate (PhI(OPiv) 2 ) C in the presence of PivOH. Indeed, the formation of C was evident from 1 H NMR of the crude reaction mixture.…”

Direct para-Selective C–H Amination of Iodobenzenes: Highly Efficient Approach for the Synthesis of Diarylamines

“…Subsequently, Hyatt 13 demonstrated that iodobenzenes can undergo para-selective benzylation via the in situ formation of hypervalent iodine intermediates using Selectfluor as the oxidant. In addition, Lei 14 has reported a two-electrontransfer oxidation-induced strategy for para-selective C−H etherification of iodosobenzenes. The iodine group can be easily transformed into other functional groups by various coupling reactions; thus, it would be useful to construct diarylamine skeletons with an iodine group.…”