Highly Efficient Synthesis of Quinoxalinone-N-oxide via Tandem Nitrosation/Aerobic Oxidative C–N Bond Formation

Abstract

An efficient method for constructing quinoxalinone-N-oxides from cyanoacetanilides has been developed. This transformation can be achieved using inexpensive reagents and molecular oxygen under mild conditions, thus offering a practical pathway to quinoxalinone-containing pharmaceuticals such as ataquimast and opaviraline.

Oxidative Radical Cyclization of N‐methyl‐N‐arylpropiolamide to Isatins via Cleavage of the Carbon‐carbon Triple Bond

“…The results show that a nitration reaction occurs along with the oxidative cyclization of 1 a , leading to the formation of non‐nitrated and nitrated products 2 a and 3 a , respectively. NaNO 2 adopts the role of a radical initiator and a nitro source ,. The treatment of 1 a with NaNO 2 (1 equiv) and K 2 S 2 O 8 (0.5 equiv) gave products 2 a and 3 a in yields of 13% and 29%, respectively (entry 1).…”

Bis(dibenzylideneacetone)palladium(0)/tert‐Butyl Nitrite‐ Catalyzed Cyclization of o‐Alkynylanilines with tert‐Butyl Nitrite: Synthesis and Applications of Indazole 2‐Oxides

“…In this context, Kimachi et al. (2011) reported the synthesis of quinoxalinone N ‐oxides from cyanoacetanilides through the in situ generation of NO using a combination of NaNO 2 /H 2 SO 4 /O 2 (Scheme a) . In 2014, Jiao et al.…”

Metal‐Free Oxidative Carbon‐Heteroatom Bond Formation Through C–H Bond Functionalization

“…Kobayashi et al discovered a highly efficient method for synthesizing quinoxalinone N ‐oxides through tandem nitrosation/aerobic oxidative cyclization of cyanoacetanilides with cheap reagents (Scheme ) 12. The cyano groups in the product could be substituted with carbon and nitrogen nucleophiles, providing easy access to differently substituted quinoxalinone derivatives including the natural products ataquimast and opaviraline.…”