170123-75-8

Upstream product

• 170123-73-6 5-methoxy-1-phenyl-2,3-dihydropyrrole-2,3-dione 
• 2055-52-9 methyl 1-phenyl-1H-1,2,3-triazole-4-carboxylate 
• 174742-20-2 2,2-dimethyl-5--1,3-dioxane-4,6-dione 

Relevant academic research and scientific papers

Imidoylketene-oxoketenimine interconversion. Rearrangement of a carbomethoxyketenimine to a methoxyimidoylketene and 2-methoxy-4-quinolone

FVP of triazole 13 produces the isolable ketenimine 11 together with indole 15. 11 undergoes reversible interconversion with imidoylketene 10 above 380 °C. The latter cyclizes to quinolone 12. Meldrum's acid derivative 16 produces the same ketene 10 above 200 °C, and the latter isomerizes to ketenimine 11 at 200 °C by a 1,3-shift of a MeO group. A competing elimination of MeOH from 16 produces (phenylimino)propadienone 20.

Imidoylketene-oxoketenimine rearrangement. Facile 1,3-shift of an alkoxy group

Thermal CO extrusion from 2,3-dihydropyrrole-2,3-dione 3 generates imidoylketene 4, which cyclizes to 2-methoxy-4-quinolone (6). Using flash vacuum pyrolysis and low temperature IR spectroscopy, it is shown that 4 interconverts with ketenimine 5 prior to cyclization to 6.