| Popis: |
Some α- and β-halonitrosoalkenes 1 have been synthesized and characterized. The halogen atoms of the oxime precursors 2 can be substituted by alkoxy groups. Two kinds of cycloaddition reaction of 1 have been observed: (i) reaction of the NO group with dienes gives 3, 6-dihydrooxazine derivatives 6 which isomerise to epoxyepimines 7 in most cases of β-substituted nitrosoalkenes; (ii) if 4, 5-dihydrooxazines 22 are obtained, the cycloaddition of the nitrosoalkenes as 4π-component is presumed. |
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