Base‐Free Selective O‐Arylation and Sequential [3, 3]‐Rearrangement of Amidoximes with Diaryliodonium Salts: Synthesis of 2‐Substituted Benzoxazoles. Issue 23 (29th September 2017)

• Record Type: Journal Article
• Authors: Shi, Wei‐Min; Li, Xiao‐Hua; Liang, Cui; Mo, Dong‐Liang
• Is Part Of: Advanced synthesis & catalysis. Volume 359:Issue 23(2017)
• Page Start: 4129
• Page End: 4135
• Publication Date: 2017-09-29
• Subjects: Amidoxime -- Benzoxazoles -- Diaryliodonium salts -- O-Arylation -- [3, 3]-Rearrangement; Catalysis -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Chemistry -- Periodicals; Chemistry, Technical -- Periodicals; Chemistry -- Periodicals; Catalysis -- Periodicals; Technology, Pharmaceutical -- Periodicals; 547.2
• DOI: 10.1002/adsc.201700906
• Languages: English
• ISSNs: 1615-4150

Abstract

Abstract: 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. Abstract :