Polycyclic nitrogen compounds. Part I. Synthesis of new heterotricyclic quinoxalinones with bridgehead nitrogen atoms

Adegoke, E.A. ; Alo, B.I. ; Ogunsulire, F.O. (1982-10)


New tricyclic quinoxalinone skeletons with a fully‐reduced ring ‘C’ ‐1,2,3,3a‐tetrahydropyrrolo[1,2‐α]quin‐oxalin‐4‐one (I‐II) and 7,8,9,10‐tetrahydropyrido[1,2‐α]quinoxalin‐6‐one (III‐IV) derivatives were obtained by selective hydrogen transfer reductive cyclisation of N‐(2‐nitrophenyl)pyrrolidine‐2‐carboxylic acid esters and N‐(2‐nitrophenyl)piperidine‐2‐carboxylic acid esters (VIa,b and VIIIa,b), respectively.