282103-89-3Relevant academic research and scientific papers
Merging gold and organocatalysis: A facile asymmetric synthesis of annulated pyrroles
Hack, Daniel,Loh, Charles C. J.,Hartmann, Jan M.,Raabe, Gerhard,Enders, Dieter
, p. 3917 - 3921 (2014/04/17)
The combination of cinchona-alkaloid-derived primary amine and Au I-phosphine catalysts allowed the selective C-H functionalization of two adjacent carbon atoms of pyrroles under mild reaction conditions. This sequential dual activation provides seven-membered-ring-annulated pyrrole derivatives in excellent yields and enantioselectivities. Outwitted: The combination of cinchona-alkaloid-derived primary amine and Au I-phosphine catalysts allowed the selective C-H functionalization of two adjacent carbon atoms of pyrroles under mild reaction conditions. This sequential dual activation provides seven-membered-ring-annulated pyrrole derivatives in excellent yields and enantioselectivities (see scheme).
Silver-catalyzed C-C bond formation with carbon dioxide: Significant synthesis of dihydroisobenzofurans
Sekine, Kohei,Takayanagi, Ayano,Kikuchi, Satoshi,Yamada, Tohru
supporting information, p. 11320 - 11322 (2013/12/04)
The silver salt catalyzed the C-C bond forming reaction of o-alkynylacetophenone derivatives and carbon dioxide. In this reaction, a carbonyl group and a furan skeleton were successively constructed to afford the corresponding dihydroisobenzofuran derivatives.
AuBr3- and Cu(OTf)2-catalyzed intramolecular [4 + 2] cycloaddition of tethered alkynyl and alkenyl enynones and enynals: A new synthetic method for functionalized polycyclic hydrocarbons
Asao, Naoki,Sato, Kenichiro,Menggenbateer,Yamamoto, Yoshinori
, p. 3682 - 3685 (2007/10/03)
(Chemical Equation Presented) Treatment of tethered alkynyl enynones 8, in which a carbon chain is attached to the carbonyl group, with a catalytic amount of AuBr3in (ClCH2)2 gave the naphthyl ketones 9 in good to high yields (top-down approach). Analogously, the AuBr 3-catalyzed benzannulations of 10, in which a carbon tether is extended from the alkynyl terminus, also proceeded smoothly, and the cyclized naphthyl ketones 11 were obtained in high yields (bottom-up approach). Similarly, when two kinds of tethered alkenyl enynones 12 and 14 were treated with Cu(OTf)2 catalyst, the corresponding dihydronaphthyl ketone products 13 and 15 were obtained in high yields, respectively. The present formal [4 + 2] intramolecular cycloaddition proceeds most probably through the coordination of the triple bond at the ortho position of substrates to Lewis acids, the formation of benzopyrylium ate complex 16 via the nucleophilic addition of the carbonyl oxygen atom, the reverse electron demand type Diels-Alder addition of the tethered alkynes or alkenes to the ate complex, and subsequent bond rearrangement.
