resumo
A mild synthesis of 3,5-disubstituted nitrobenzenes from readily available 3-formylchromones is reported. The developed methodology follows a cascade process, promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene. The proposed mechanism involves an initial Michael addition of nitromethane at C-2 of a 3-formylchromone. The resultant intermediate undergoes another Michael reaction with a second 3-formylchromone molecule. After ring closure through intramolecular cyclization, the aromatization is completed by deformylation, affording the 3,5-disubstituted nitrobenzenes in 52-86% yield. The reported method produces three new C-C bonds in a simple and straightforward manner, and it is consistent with gram-scale synthesis.
palavras-chave
OXIDATION
categoria
Chemistry
autores
Francisco, TN; Sousa, JLC; Guieu, S; Silva, AMS; Albuquerque, HMT
nossos autores
Joana Lia Cardoso de Sousa
Bolseiro de pós-Doutoramento
Samuel Jacques André Guieu
Investigador JúniorGrupos
1 - nanomateriais inorgânicos funcionais e híbridos orgânico-inorgânico
4 - biorrefinarias, materiais de origem biológica e reciclagem
agradecimentos
This work was financed by Portugal 2020 through FEDER in the framework of POCI and in the scope of the projects EpigenGlicON (POCI-01-0145-FEDER-029767), LAQV-REQUIMTE (UIDB/50006/2020), and CICECO -Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020), co-financed by FCT/MCTES. J.S., H.A., and T.F. acknowledge the EpigenGlicON project (POCI-01-0145-FEDER029767) for their researcher contracts and research grant, respectively.