623548-10-7Relevant academic research and scientific papers
R4NHal/NOHSO4: A Usable System for Halogenation of Isoxazoles, Pyrazoles, and beyond
Bondarenko, Oksana B.,Karetnikov, Georgy L.,Komarov, Arseniy I.,Pavlov, Aleksandr I.,Nikolaeva, Svetlana N.
, p. 322 - 332 (2021)
A new convenient and versatile halogenating system (R4NHal/NOHSO4), giving straightforward and general access to halogenated 3,5-diaryl- and alkylarylisoxazoles, pyrazoles and electron-rich benzenes from the corresponding scaffolds, is suggested. The method provides excellent regioselectivity, scalability to the gram scale, and a broad scope for both aromatics and halogens. A three-step, one-pot reaction protocol was developed, and a series of 3,5-diaryl-4-haloisoxazoles has been efficiently synthesized from 1,2-diarylcyclopropanes under suggested nitrosating-halogenating conditions.
Convenient and improved halogenation of 3,5-diarylisoxazoles using N-halosuccinimides
Day, Ruth Ann,Blake, Jacqueline A.,Stephens, Chad E.
, p. 1586 - 1590 (2007/10/03)
The convenient C-4 halogenation of 3,5-diarylisoxazoles using N-halosuccinimides (NBS, NCS, or NIS) in acetic acid is described. A strong acid catalyst was required for efficient halogenation of some isoxazoles depending on the substituent on the 5-phenyl ring. Finally, the 4-iodoisoxazoles were found to undergo a novel proto-deiodination upon heating in the presence of H2SO4.
