Mechanistic Insights into the One‐Pot Synthesis of Propargylamines from Terminal Alkynes and Amines in Chlorinated Solvents Catalyzed by Gold Compounds and Nanoparticles

Abstract

Propargylamines can be obtained from secondary amines and terminal alkynes in chlorinated solvents by a three- and two-component synthesis catalyzed by gold compounds and nanoparticles (Au-NP) under mild conditions. The use of dichloromethane allows for the activation of two C-Cl bonds and a clean transfer of the methylene fragment to the final product. The scope of the reaction as well as the influence of different gold(III) cycloaurated complexes and salts has been investigated. The involvement of gold nanoparticles generated in situ in the process is discussed and a plausible reaction mechanism is proposed on the basis of the data obtained.

Unexpected formation of a fused double cycle trinuclear gold(i) complex supported by ortho-phenyl metallated aryl-diphosphine ligands and strong aurophilic interactions

“…Dinuclear [Au2(L)(Cl)] + species derived upon C-Cl bond cleavage of dichloromethane were observed in the ESI MS spectrum at m/z 1007 ( Figure S6). While a variety of dinuclear gold(II) and mononuclear gold(III) compounds were prepared by gold(I)-mediated oxidative addition of dichloromethane, 10,11 this is a rare observation of formation of a gold(I) halide complex by activation of the C-Cl bond in CH2Cl2. Schmidbaur and Fackler studied extensively the oxidative addition of dihalomethanes CH2X2, halogens X2 (X = Cl, Br and I) and alkyl halides to eight-membered dinuclear gold(I) ylide complexes, [Au2(CH2PR2CH2)]2.…”

Phosphine/phenylacetylide-ligated Au clusters for multicomponent coupling reactions

“…Of note, the iminium ion is an intermediate produced by an aldehyde and an amine in the reaction media. Gold clusters with active sites in different oxidation states (Au III , Au I , and Au 0 ) have emerged as a new promising class of catalysts for carbon-carbon coupling and other related reactions [15][16][17][18][19][20][21][22][23]. However, partly due to the polydispersity issues of gold clusters, it is difficult to establish definitive structure-activity relationships for nanogold-catalyzed reactions, posing a challenge to systematic development and application of gold cluster catalysts.…”

Cytotoxic hydrophilic iminophosphorane coordination compounds of d8 metals. Studies of their interactions with DNA and HSA

“…We and others have reported on the biological [15–18] and catalytic [19–21] applications of iminophosphorane or iminophosphine derivatives of gold(III) (selected examples in Fig. 1) [15,16].…”