RESUMO
An I2-mediated approach for selective C-H functionalization of unprotected aniline derivatives for synthesizing benzils and quinoxaline derivatives from sulfoxonium ylides has been described. Aniline derivatives and sulfoxonium ylides ornamented with different functional groups showed good compatibility. They afforded the corresponding products with moderate to high yields via a mild and simple procedure. Finally, we validated the practicality of this method by scaling up the reaction and further conversion of the synthesized derivatives into other valuable molecules.
RESUMO
A novel straightforward and catalyst-free approach for synthesizing quinoxaline derivatives from sulfoxonium ylides and o-phenylenediamines mediated by elemental sulfur has been described. Due to the simple and mild reaction conditions, the sulfoxonium ylides and o-phenylenediamines decorated with different functional groups furnished moderate to high yields of quinoxaline derivatives and were well tolerated. Finally, large-scale reactions, the synthesis of pyrazines, and some bioactive compounds are used to illustrate the potential utility of the developed approach.
RESUMO
An efficient base, additive and metal-free synthetic methods for α-ketothioamide and α-ketoamide derivatives from readily available sulfoxonium ylides have been described. Sulfoxonium ylides with primary or secondary amines afforded α-ketothioamides in the presence of elemental sulfur, whereas α-ketoamides were produced when I2 and TBHP were present. The reaction proceeded well at room temperature and generated the corresponding molecules in good to excellent yields. The reaction can be scaled-up and tolerated by a range of functional groups with simple operational procedures.
