Cesium Hydroxide: A Superior Base for the Catalytic Alkynylation of Aldehydes and Ketones and Catalytic Alkenylation of Nitriles

The efficient addition of terminal alkynes to aldehydes or ketones to give propargyl alcohols in yields of 66–96 % can be achieved by activation with catalytic amounts of CsOH⋅H₂O Eq. (a)]. A CsOH-catalyzed addition of acetonitrile derivatives to terminal alkynes is also possible.