Copper Powder-Mediated Tandem Hydroamination Cyclization-Hydrocyanation of Alkyne-Tethered Ketoximes toward Cyano-Featured Cyclic Nitrones

The copper powder-mediated tandem hydroamination cyclization-hydrocyanation of alkyne-tethered ketoximes is described by using TMSCN as the commercially available cyanating reagent. This methodology provides an alternative strategy for the synthesis of a series of structurally important cyano-substituted cyclic nitrones. The hydrocyanation process exhibits distinct regioselectivity depending on the substituent pattern of the alkyne moiety. Moreover, the synthesized products were shown to be capable of undergoing various derivatization reactions.