Heteroatomfunktionalisierte Methylgold-Komplexe: Synthese und Struktur von Chlormethyl(triphenylphosphin)- und Phenylthiomethyl(trimethylphosphin)gold

Gold Sulfonium Benzylide Complexes Undergo Efficient Benzylidene Transfer to Alkenes

“…[20][21][22] However,e xtracting detailed mechanistic information relevant to catalysis from these stoichiometric carbene transfer processes is complicated by the (1) excessive stabilization of the carbene complex, (2) in situ generation of the carbene complex with strong Lewis acids underc ryogenic conditions, and/or( 3) the extreme facility of carbene transfer. [18,25,26] However carbene transferf rom F requiresf orcingc onditions and as tabilizing C1 anisyl group for spontaneous activation and undergoes irreversible carbene formation, all of whichw ould complicate kinetic andm echanistic analysiso fc arbene transfer. [18,25,26] However carbene transferf rom F requiresf orcingc onditions and as tabilizing C1 anisyl group for spontaneous activation and undergoes irreversible carbene formation, all of whichw ould complicate kinetic andm echanistic analysiso fc arbene transfer.…”

“…[29][30][31][32] Initial efforts to synthesize gold sulfonium benzy- lide complexes by S-alkylation of gold a-thiobenzyl complexes [26,27] or throughl igand displacementw ith sulfonium benzylides [28] proved unsuccessful. However,athird approach involving nucleophilic substitution of ag old a-chlorobenzyl carbenoid complex with sulfide, whichw as modelled after similar transformations reported by Steinborn [26] and Echavarren, [24] provede ffective. In an optimized procedure, treatment of (P1)AuCHClPh [24] [P1 = P(tBu) 2 o-biphenyl] with sodium tetrakis [3,5-bis(trifluoromethyl)phenyl]borate (NaBAr F 4 ,1 .1 equiv) and excesst etrahydrothiophene (THT,1 0equiv) in toluenea t room temperature led to the isolation of gold (tetramethylene)sulfonium benzylide complex[ ( P1)AuCHPh(THT)] + BAr F 4 À (1a)i n6 8% yield after crystallization (Scheme 1).…”

Nucleophilic T-Shaped (LXL)Au(I)-Pincer Complexes: Protonation and Alkylation

“…The X-ray diffraction study of crystals obtained in CD 2 Cl 2 revealed a short N-Au bond distance [2.078(5) Å] as observed in the Au­(III)-hydride 2 a , but the expected square-planar geometry is significantly distorted [N-Au-C 166.2(2)°], possibly because of excessive steric bulk (Figure b). Note that a chloromethyl gold complex has previously been prepared by salt metathesis from the Grignard reagent . The oxidative addition of CH 2 X 2 to gold was previously only observed with binuclear gold dimers leading to mixed Au­(I)/Au­(III) compounds …”