Synthesis of <i>N</i>-Sulfonyl Acetamidine Using Calcium Carbide as the Alkynyl Source and Ammonium Bicarbonate as the Amine Source

A new approach for the efficient synthesis of <i>N</i>-sulfonyl acetamidine via a one-pot multicomponent reaction at room temperature using calcium carbide as the alkyne source and ammonium bicarbonate as the amine source with sulfonyl azides is reported. The method efficiently constructed two bonds (C-N and C═N) in the aqueous system and has the advantages of cheap and easy availability of raw materials, mild conditions, simple operation, wide scope of substrates, convenient scale-up to gram scale, and potential industrial applications.