1370372-11-4Relevant articles and documents
Synthesis of Naphthalenyl Triflates via the Cationic Annulation of Benzodiynes with Triflic Acid
Ge, Chenxin,Wang, Guohua,Wu, Panpan,Chen, Chao
, p. 5010 - 5014 (2019/07/08)
A highly efficient and regioselective annulation of benzodiynes promoted by triflic acid has been developed. This protocol provides a step and atom-economic access to a series of naphthalenyl triflates. Furthermore, direct synthetic applications of this r
Insights into the Gold-Catalyzed Propargyl Ester Rearrangement/Tandem Cyclization Sequence: Radical versus Gold Catalysis - Myers-Saito- versus Schmittel-Type Cyclization
Rettenmeier, Eva,Hansmann, Max M.,Ahrens, Alexander,Rübenacker, Katharina,Saboo, Tapish,Massholder, Joy,Meier, Christian,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 14401 - 14409 (2015/10/05)
A detailed study of the gold-catalyzed tandem 1,3-carboxy migration/allene-enyne cycloisomerization was undertaken. It was found that after the initial allene formation the selectivity of the reaction is strongly influenced by the polarization of the remaining alkyne. Depending on the substitution pattern of the starting diynes, either a Schmittel- or a Myers-Saito-type cyclization was triggered. The 6-endo-dig Myers-Saito-type cyclization gave access to benzo[b]fluorenes, while the Schmittel pathway (5-exo-dig) delivered benzofulvenes as final products. In special cases a yet unknown pathway was opened by the ambiphilic nature of the allene moiety. In these cases completely different products were obtained by the nucleophilic attack of the alkyne moiety onto the allene that can also act as an electrophile. Mechanistic studies revealed that diradical pathways can be ruled out for this type of tandem cyclization reactions and it is shown that both steps of the reaction cascade are catalyzed by the gold complex.
CO extrusion in homogeneous gold catalysis: Reactivity of gold acyl species generated through water addition to gold vinylidenes
Bucher, Janina,St?sser, Tim,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 1666 - 1670 (2015/01/30)
Herein, we describe a new gold-catalyzed decarbonylative indene synthesis. Synergistic σ,π-activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneous gold catalysis. By tuning the electronic and steric properties of the starting diyne systems, this new reactivity could be exploited for the synthesis of indene derivatives in high yields.
Gold-catalyzed synthesis of dibenzopentalenes - Evidence for gold vinylidenes
Hashmi, A. Stephen K.,Wieteck, Marcel,Braun, Ingo,Noesel, Pascal,Jongbloed, Linda,Rudolph, Matthias,Rominger, Frank
, p. 555 - 562 (2012/04/17)
A series of easily accessible arene-1,2-diynes, bearing one aryl substituent on one of the alkynyl groups, is readily converted to dibenzopentalenes in good yields by gold(I) catalysts. The participation of gold acetylides could be proven by the direct conversion to the corresponding gem-diaurated dibenzopentalenes with a gold catalyst. From an experiment with a gold acetylide complex and stoichiometric amounts of the gold "catalyst" the corresponding gem-diaurated complex of a dibenzopentalene could be obtained and characterized by X-ray crystal structure analysis. Labelling studies with deuterated alkynes show the expected deuteration of the two remaining positions of the pentalene core. All this provides evidence for a dual activation mode of the reaction and gold(I) vinylidene complexes as intermediates of the catalytic cycle. Copyright
