Polyfunctionalized biaryls accessed by a one-pot nucleophilic aromatic substitution and sigmatropic rearrangement reaction cascade under mild conditions

• Published in: Tetrahedron Vol. 83; pp. 131966 - 131975
• Main Authors: Liang, Dong-Dong, Guo, Shen-Yi, Tong, Shuo, Wang, Mei-Xiang
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 12.03.2021; Elsevier
• Subjects: [3,3]-sigmatropic rearrangement; [5,5]-sigmatropic rearrangement; Biaryl; Chemistry; Chemistry, Organic; N,O-diarylhydroxylamine; Physical Sciences; Science & Technology; SNAr reaction; N,O-diarylhydroxylamine; SNAr reaction; [3,3]-sigmatropic rearrangement; [5,5]-sigmatropic rearrangement; Biaryl
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2021.131966

A practical synthetic method has been developed for polyfunctionalized biaryls based on a facile one-pot nucleophilic aromatic substitution (SNAr) reaction and [5,5]- or [3,3]-sigmatropic rearrangement reaction cascade. Under mild basic conditions, N-arylhydroxylamines reacted with o-activated fluoro (het)arenes to form N,O-diarylhydroxylamine intermediates which underwent spontaneously selective [5,5]-sigmatropic rearrangement reaction to produce diverse functionalized 4-amino-4′-hydroxy-1,1′-biaryls. A sequential SNAr reaction and [3,3]-sigmatropic rearrangement took place between N-arylhydroxylamines and 2-fluoropyridine derivatives or 4-fluorobenzonitrile to afford functionalized 2-amino-2′-hydroxy-1,1′-biaryls. As invaluable and unique building blocks, the resulting biaryls were applied in the straightforward synthesis of N2,O2-coronarene, carbazole, aza- and diaza carbazole derivatives. [Display omitted]