Isothiocyanates other multiple bonds

Electron-poor multiple bonds in acetylene dicarboxylates42 137 149), ketenes 150 152> isocyanates, isothiocyanates, carbodiimides 138-153) and arynes42) add metallated ynamines to give adducts that still carry the ynamine moiety. This behaviour contrast with that of other ynamines which mostly undergo various cycloadditions but it must be stressed that even here cycloadducts may be formed as by-products. 

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