Zinc-Catalyzed Synthesis of Functionalized Furans and Triarylmethanes from Enynones and Alcohols or Azoles: Dual XH Bond Activation by Zinc
作者:Jesús González、Javier González、Carmela Pérez-Calleja、Luis A. López、Rubén Vicente
DOI:10.1002/anie.201301625
日期:2013.5.27
Ba'zinc'ga! A zinc‐catalyzed sequence involving a cyclization with a subsequent CO, CN, or CC bond formation enables the preparation of a variety of valuable furfuryl ethers (with alcohols) and unsymmetrically substituted triarylmethane derivatives (with azoles or arenes). ZnCl2 serves as the catalyst.
Palladium-catalyzed cross-coupling reactions between benzyl, aryl, or allyl bromides and conjugated ene-yne-ketones lead to the formation of 2-alkenyl-substituted furans. This novel coupling reaction involves oxidative addition, alkyne activation-cyclization, palladium carbene migratoryinsertion, β-hydride elimination, and catalyst regeneration. Palladium (2-furyl)carbene is proposed as the key intermediate
A convenient one-pot Cu(I)-catalyzed strategy for regioselective synthesis of trisubstituted furan derivatives has been developed via (2-furyl) carbenecomplexes. This process has opened a new synthetic route to a variety of α-carbonyl furans using air as the oxidant affording furans in good yields.
Catalytic Generation of Zinc Carbenes from Alkynes: Zinc-Catalyzed Cyclopropanation and SiH Bond Insertion Reactions
作者:Rubén Vicente、Jesús González、Lorena Riesgo、Javier González、Luis A. López
DOI:10.1002/anie.201203914
日期:2012.8.6
Think zinc: Synthetically relevant zinc(II) carbenes are catalytically generated fromalkynes (see scheme). This new approach allows zinc‐catalyzed cyclopropanation and SiHbondinsertionreactions to generate the corresponding cyclopropylfurans or silane derivatives. The structure of the key carbene intermediate was studied using theoretical methods.
Zinc-Catalyzed Functionalization of SiH Bonds with 2-Furyl Carbenoids through Three-Component Coupling
作者:Sergio Mata、Luis A. López、Rubén Vicente
DOI:10.1002/chem.201501155
日期:2015.6.15
A three‐component coupling of alk‐2‐ynals, 1,3‐dicarbonyls and silanes is reported. ZnCl2 serves as an inexpensive and low‐toxic catalyst for the overall transformation, which involves Knoevenagel condensation, cyclization, and carbene SiH bond insertion. The process takes place with high atom economy in the absence of organic solvents and shows a broad scope. This reaction is also applicable to the