In the presence of Na2CO3, the [3+2] cycloaddition of azaoxyallyl cations, in situ formed from α‐halohydroxamates by reaction with isothiocyanides, proceeded smoothly and furnished (Z)‐2‐iminothiazolidin‐4‐ones in 25–99 % chemical yields. The chemical structure of the title compounds was confirmed by X‐ray single‐crystal structure analysis.