Regioselective Synthesis of Functionalized Pyrroles<i>via</i>Gold(I)-Catalyzed [3+2] Cycloaddition of Stabilized Vinyl Diazo Derivatives and Nitriles
作者:Giacomo Lonzi、Luis A. López
DOI:10.1002/adsc.201300346
日期:2013.7.8
The reaction of nitriles with alkenyldiazo compounds in the presence of gold catalysts provides functionalized pyrrole derivatives in moderate to high yields. This formal [3+2] cyclization reaction takes place with complete regioselectivity. The observed regiochemical outcome suggests the attack of the nitrile to the terminal position of the alkenylgold carbenoid (vinylogous reactivity). A broad range
Gold-catalyzed α-furanylations of quinoline N-oxides with alkenyldiazo carbonyl species
作者:Vinayak Vishnu Pagar、Rai-Shung Liu
DOI:10.1039/c5ob00696a
日期:——
Gold-catalyzed α-furanylations of 8-alkylquinoline N-oxides have been achieved using alkenyldiazo carbonyl species as nucleophiles. The reactions are applicable to a reasonable range of alkenyldiazo species and 8-alkylquinoline N-oxides. The reaction mechanism is postulated to involve an initial nucleophilic addition of diazocarbonyl species at 8-alkylquinoline N-oxides, followed by diazo decomposition.
Zinc-Catalyzed Synthesis of Conjugated Dienoates through Unusual Cross-Couplings of Zinc Carbenes with Diazo Compounds
作者:Sergio Mata、María J. González、Jesús González、Luis A. López、Rubén Vicente
DOI:10.1002/chem.201604194
日期:2017.1.23
of two carbene sources, such as vinyl diazocompounds and enynones, enabled the synthesis of conjugated dienoate derivatives. This reaction involved the unprecedented coupling of a zinc furyl carbene with vinyl diazocompoundsthrough the γ‐carbon. Alternatively, dienoates were also prepared by a commutative cross‐coupling of zinc vinyl carbenes generated from cyclopropenes and simple diazo compounds
Gold-Catalyzed Cycloaddition Reactions of Ethyl Diazoacetate, Nitrosoarenes, and Vinyldiazo Carbonyl Compounds: Synthesis of Isoxazolidine and Benzo[<i>b</i>]azepine Derivatives
作者:Vinayak Vishnu Pagar、Rai-Shung Liu
DOI:10.1002/anie.201500340
日期:2015.4.13
Gold‐catalyzed cycloadditions of ethyldiazoacetate, nitrosoarenes, and vinyldiazo carbonyl species to yield isoxazolidine derivatives stereoselectively are described. Treatment of these isoxazolidine products with the same catalyst results in a novel 1,2‐H shift/[3,3] rearrangement to give benzo[b]azepine compounds. The mechanism of this skeletal rearrangement is elucidated with deuterium‐labeling
Gold-Catalyzed Reactions between Alkenyldiazo Carbonyl Species and Acetals
作者:Vinayak Vishnu Pagar、Appaso M. Jadhav、Rai-Shung Liu
DOI:10.1021/jo400419d
日期:2013.6.7
In the presence of catalyst IPrAuSbF6 catalyst (IPr = 1,3-bis(diisopropylphenyl)imidazol-2-ylidene), alkenyldiazo carbonyl species react with organic acetals to give E-configured alkyl 3,5-dimethoxy-5-pent-2-enoates stereoselectively. This reaction sequence comprises an initial Prins-type reaction, followed by gold carbene formation.