Triphenylphosphine-Catalyzed [3+2] Cycloaddition of Allenoate and Active Olefins: Syntheses of Spirooxindole Derivatives
作者:Xueshun Jia、Shanyan Guo、Rendong Wang、Jian Li、Chunju Li、Hongmei Deng
DOI:10.1055/s-0030-1261188
日期:2011.9
A series of spiro compounds was achieved by triphenylphosphine-catalyzed [3+2] cycloaddition between active methylenemalononitrile and ethyl 2,3-butadienoate. Careful investigation showed that the present method had high regioselectivity. The products have a spirooxindole skeleton, which is a motif common in many natural products and pharmaceutically active compounds.
promising asymmetric synthesis of highly functionalized 2-oxospiro-[indole-3,4′-(1′,4′-dihydropyridine)] via the reaction of an enamine with isatylidenemalononitrile derivatives in the presence of a chiral base organocatalyst. The moderate, but promising, enantioselectivity observed (30%–58% ee (enantiomeric excess)) opens the door to a new area of research for the asymmetricconstruction of these
Palladium-Catalyzed Bis-Functionalization of Isatylidenes: A Facile Route towards Spiro-Indol-2-ones
作者:Sholly Clair George、Jubi John、Saithalavi Anas、Joshni John、Yoshinori Yamamoto、Eringathodi Suresh、K. V. Radhakrishnan
DOI:10.1002/ejoc.201000604
日期:——
construction of 3,3-disubstituted indol-2-ones from isatylidenes by utilizing amphiphilic bis-π-allylpalladium and related intermediates. The developed strategy is a new method for the quaternization of position 3 of the indol-2-one towards disubstituted functionalized indol-2-ones. These products were subjected to ring-closing metathesis towards the synthesis of spiro[cyclohexene-1,3′-indol]-2′-ones