Ceric ammonium nitrate (CAN) mediated novel dimerizations of 4-hydroxyquinolin-2(1H)-ones: the first example of reactions of oxygen-centered radicals from 1,3-dicarbonyl compounds

摘要

Reactions of 4-hydroxyquinolin-2(1H)-ones (1) and 3-alkylated 4-hydroxyquinolin-2(1H)ones (2) with CAN in methanol gave quinolin-2(1H)-one dimers 3, 10 and 11 with C-C and C-O linkages between the two nitrogen containing sis-member rings, respectively, showing the ambident reactivities of alpha,alpha'-dicarbonylalkyl radicals as carbon- and oxygen-centered radicals. (C) 1999 Elsevier Science Ltd. All rights reserved. [References: 38]