2-Azetine, 1-methoxycarbonyl

The double bond in A7-methoxycarbonyl-2-azetine (237 Z = COaMe) undergoes acid or photocatalyzed hydration and subsequent ring opening to give the aldehyde (238). In cycloadditions it is inert to TCNE and diphenylisobenzofuran but it does react with dipyridyltetrazine (77CC806). 

N-Methoxycarbonyl-A- -azetine reacted with a tetrazine at room temperature to give predominantly a substituted pyridazine. The reaction involves ring scission of the azetidine ring (77CC806). 

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