Electrospray Ionization Tandem Mass Spectrometry and DFT Survey of Copper(I) Ate Complexes Containing Coordinated Borohydride Anions

Abstract

Copper(I) borohydride ate complexes of the type Cat+[XCu(BH4)]- have been previously postulated as intermediates in the reactions of copper salts with borohydride. Negative ion electrospray ionization of an acetonitrile solution of copper(I) phenylacetylide with a 10-fold excess of sodium borohydride (NaBH4) revealed the formation of a diverse range of mononuclear, dinuclear and trinuclear cuprates with different numbers of BH4-, H- and CN- ligands, the latter likely being formed by abstraction of CN- from the acetonitrile solvent. Collision-induced dissociation was used to examine the fragmentation reactions of the following borohydride containing cuprates: [Cu(H)(BH4)]-, [Cu(BH4)2]-, [Cu(B..