H. Barjesteh et al., REACTION OF 1,2-QUINONE MONOOXIMES AND THEIR METAL-COMPLEXES WITH DIMETHYL ACETYLENEDICARBOXYLATE, Journal of chemical research. Synopses, (11), 1995, pp. 454
1,2-Quinone monooximes (1) and their metal complexes (2) react with di
methyl acetylenedicarboxylate (DMAD) under relatively mild conditions
to give 1,4-oxazines (3) or 1,4-oxazin-2-ones (4) or the nucleophilic
1,2-addition products (Z)- and (E)-1,2-benzoquinone 1-{O-[1,2-bis(meth
oxycarbonyl)ethyenyl]oxime} (5 and 6) or 1,3-oxazoles (7).