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Base‐Free Selective O ‐Arylation and Sequential [3,3]‐Rearrangement of Amidoximes with Diaryliodonium Salts: Synthesis of 2‐Substituted Benzoxazoles
Author(s) -
Shi WeiMin,
Li XiaoHua,
Liang Cui,
Mo DongLiang
Publication year - 2017
Publication title -
advanced synthesis and catalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.541
H-Index - 155
eISSN - 1615-4169
pISSN - 1615-4150
DOI - 10.1002/adsc.201700906
Subject(s) - chemistry , amide , amine gas treating , aryl , denticity , aldehyde , combinatorial chemistry , halide , base (topology) , ligand (biochemistry) , medicinal chemistry , organic chemistry , metal , alkyl , catalysis , mathematical analysis , mathematics , biochemistry , receptor
A variety of functionalized 2‐substituted benzoxazoles can be prepared in good yields from amidoximes and diaryliodonium salts by selective O ‐arylation and sequential [3,3]‐rearrangement under metal‐free conditions. O ‐arylation of amidoximes was promoted by 3 Å molecule sieves in the absence of a base and a sequential TFA‐mediated [3,3]‐rearrangement was used to synthesize 2‐substituted benzoxazoles. Both of the O ‐aryl products and rearrangement products were compatible with a broad range of sensitive functional groups such as ester, aldehyde, nitro, vinyl, amine, and amide groups in addition to halides. A bidentate N ‐ligand with double benzoxazoles was prepared at gram‐scale in two steps.