Cleavage of X−H Bonds (X = N, O, or C) by Copper(I) Alkyl Complexes To Form Monomeric Two-Coordinate Copper(I) Systems

The monomeric copper(I) alkyl complexes (IPr)Cu(R) [R = Me or Et; IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene] react with substrates that possess N-H, O-H, and acidic C-H bonds to form monomeric systems of the type (IPr)Cu(X) (X = anilido, phenoxide, ethoxide, phenylacetylide, or N-pyrrolyl) and methane or ethane. Solid-state X-ray crystal structures of the anilido, ethoxide, and phenoxide complexes confirm that they are monomeric systems. Experimental studies on the reaction of (IPr)Cu(Me) and aniline to produce (IPr)Cu(NHPh) suggest that a likely reaction pathway is coordination of aniline to Cu(I) followed by proton transfer to produce methane and the copper(I) anilido complex.