Switchable highly regioselective synthesis of 3,4-dihydroquinoxalin-2(1H)ones from o-phenylenediamines and aroylpyruvates

• Juraj Dobiaš,
• Marek Ondruš,
• Gabriela Addová and
• Andrej Boháč

Beilstein J. Org. Chem. 2017, 13, 1350–1360, doi:10.3762/bjoc.13.132

• could expand the synthetic impact of our results. Keywords: controlled regioselectivity; cyclocondensation; 3,4-dihydroquinoxaline-2(1H)one; HOBt/DIC; mechanism; Introduction The quinoxalin-2(1H)-one moiety is frequently found in compounds that exhibit biological activity, particularly antimicrobial

• synthesis of the desired regioisomer of 3,4-dihydroquinoxaline-2(1H)-one 16 or 17 with the best selectivity (activation of 12a,b by acid or opposite selectivity obtained from activated species 12c,d) (Scheme 6, Table 2). A limitation for regioselectivity is the fact that it is dependent on the character of

• . The guide for reaction conditions for obtaining the desired regioisomer of 3,4-dihydroquinoxaline-2(1H)one 16 (SYN) or 17 (ANTI) with the best selectivity. Supporting Information Supporting Information File 156: Additional experimental and characterisation data. Acknowledgements This research was