Group-4 Metallocene Cation Complexes of Oligopeptides: Reaction of [Cp2ZrCH3(THF)+BPh4-] with Boc-Protected Di- and Tripeptide Esters

Various gold(I) complexes of aliphatic amines have been prepared by the reaction of chloro(tetrahydrothiophene)gold(I) with the respective amines. The stability of these complexes can be attributed partly to the formation of hydrogen bonds involving the N-H functions, and partly to aurophilic interactions. Analysis of these secondary contacts suggests an inverse correlation between lengths of aurophilic interactions and hydrogen bonds.