The synthesis of 3-functionalized 5-chloro-6-methyl-2H-1,4-oxazin-2-ones and of pyridines from cycloaddition-elimination reactions with substituted acetylenic compounds

Article abstract of DOI:10.1016/S0040-4020(01)90431-4

Selective functionalisation of the chlorimine group in 3,5-dichloro-6-methyl-2H-1,4-oxazin-2-one is usually realised in appropriate conditions, by electrophilic catalysis avoiding reaction of the lactone function. The azadiene system in the 3-substituted