Synthesis and Reactivity of Gold–Olefin Complexes

Abstract

Gold catalysts have been used at an increasing frequency to facilitate a wide variety of organic transformations in synthetic organic chemistry. Among these, the functionalization of CC multiple bonds (alkenes or alkynes) in the presence of gold catalysts are some of the most important strategies utilized for the construction of CC, CO and CN bonds. A majority of these reactions are believed to proceed via gold‐bound alkene (olefin) or alkyne intermediates. This chapter highlights some of the recent developments on the syntheses of gold‐olefin complexes and their spectroscopic data and structural features. In addition, gold mediated inter‐ and intra‐molecular nucleophilic addition reactions of nitrogen, oxygen or carbon nucleophiles to olefins are discussed. Reaction mechanisms of these nucleophilic addition reactions, in which goldolefin adducts have been proposed as intermediates, are also presented.

Isolable Ethylene Complexes of Copper(I), Silver(I), and Gold(I) Supported by Fluorinated Scorpionates [HB{3‐(CF3),5‐(CH3)Pz}3]– and [HB{3‐(CF3),5‐(Ph)Pz}3]–

“…Tris(pyrazolyl)borates have played a crucial role in group 11 metal (Cu, Ag, Au) ethylene chemistry. For example, the first structurally authenticated ethylene adducts of copper, [HB{3,5‐(CH 3 ) 2 Pz} 3 ]Cu(C 2 H 4 ), silver, [HB{3,5‐(CF 3 ) 2 Pz} 3 ]Ag(C 2 H 4 ), and gold, [HB{3,5‐(CF 3 ) 2 Pz} 3 ]Au(C 2 H 4 ) involve the use of tris(pyrazolyl)borate supporting ligands , , . Fluorinated ligand analog of the copper‐ethylene adduct [HB{3,5‐(CF 3 ) 2 Pz} 3 ]Cu(C 2 H 4 ) is also known .…”

Gold‐Mediated Isomerization of ­Cyclooctyne to Ring Fused Olefinic Bicycles

“…[1][2][3][4][5][6][7][8][9][10][11][12] Cycloisomerization chemistry of 1,n-enynes, in which the alkene acts as the nucleophile towards an alkyne activated by gold(I) is particularly interesting since such reactions lead to intricate scaffolds in an atom economical manner. [1,5,6] An area of major research focus in recent years has been the chemistry of isolable alkyne-gold [13,14] and alkene-gold [13,[15][16][17] complexes since they serve as useful models for key intermediates believed to present in the above mentioned processes. There are several structurally characterized, auxiliary ligand supported and auxiliary ligand free goldalkyne [14,[18][19][20][21][22][23][24][25][26] and gold-alkene adducts presently known.…”