Titanium-Catalyzed Hydroamination of an Organometallic Acetylide to Access Copper Enamides

Abstract

In the presence of a bis-amidate bis-amido titanium precatalyst, an NHC-supported Cu acetylide was reacted with p-toluidine to cleanly generate a Cu enamido complex. The organometallic product of hydroamination was fully characterized, including X-ray single-crystal diffraction. Mechanistic investigations were undertaken to test the hypothesis that this organometallic reagent is compatible with a [2 + 2] cycloaddition mechanism for early-transition-metal-catalyzed hydroamination. This represents an unexpected functional group compatibility of this titanium precatalyst.