Synthesis, structure, and reactivity studies of ketenylidene, carbide, carbynoid, carbenoid, and tetrazolyl complexes of gold

Abstract

Chapter 1 gives a brief introduction to the topic of main group element bridged gold(I) clusters, the effects of aurophilic attraction on gold(I) cluster formation, and gold(I) carbene chemistry. An isolobal analogy is drawn between carbonate, triaryl carbeniums, gold(I) diaryl carbenes, and trigold(I) carbido cations. Chapter 2 describes the synthesis of a trigold(I) ketenylidene cation with an unexpectedly strong Au3C-CO bond. Ketene transfer reactivity is also described. Chapter 3 describes the reactivity of NHC-supported gold(I) (trimethylsilyl)diazomethyl complexes to form solvent adducts of digold(I) trimethylsilyl(methylidyne), digold(I) methylidyne, and trigold(I) carbido cations. A gold(I) methoxymethyl complex was also formed. The pyridine adduct of the trigold(I) carbido cation exhibited electrophilic reactivity toward CO to form a trigold(I) ketenylidene cation. Trapping experiments suggest the transient formation of a free trigold(I) carbido cation in non-coordinating solvents. Chapter 4 describes the auration of tetrazole to form an isomeric mixture of 1-auro(tetrazolate) and 2-auro(tetrazolate). Addition of a gold(I) triflate to the mixture affords a fluxional cationic N,N'-diauro(tetrazolate). 1,3-Dipolar cycloaddition of a terminal gold(I) azide with acetonitrile-d3 to form a 1-auro(5-methyltetrazolate)-¬d3 is also described. Chapter 5 recounts the conclusions drawn in chapters 2-4.