Synthesis of anti and syn hydroxy-iso-evoninic acids
作者:Sarah A. Warren、Stephen Stokes、Christopher S. Frampton、Andrew J. P. White、Alan C. Spivey
DOI:10.1039/c2ob25625h
日期:——
The first synthesis of hydroxy-iso-evoninic acid (2), a pyridyl diacid found as a macrodilactone bridging ligand in bioactive Celastraceae sesquiterpenoid-based natural products, has been achieved in 9 steps and an overall yield of 26%. The synthesis utilizes a benzilic ester rearrangement (BER) and a late stage benzylic oxidation to give access to all four stereoisomers whose absolute stereochemistry was assigned following chromatographic separation and anomalous dispersion X-ray crystallography.
[Cu(NHC)]-Catalyzed C−H Allylation and Alkenylation of both Electron-Deficient and Electron-Rich (Hetero)arenes with Allyl Halides
作者:Weilong Xie、Sukbok Chang
DOI:10.1002/anie.201510180
日期:2016.1.26
a [Cu(NHC)] (NHC=N‐heterocyclic carbene) catalyst is disclosed for the efficient C−H allylation of polyfluoroarenes using allyl halides in benzene at room temperature. The same catalyst system also promotes an isomerization‐induced alkenylation of initially the generated allyl arenes when the reaction is run in tetrahydrofuran. Significantly, not only electron‐deficient but also electron‐rich (hetero)arenes
A Facile Access to Pyrroles from Amino Acids via an Aza-Wacker Cyclization
作者:Zuhui Zhang、Jintang Zhang、Jiajing Tan、Zhiyong Wang
DOI:10.1021/jo800433b
日期:2008.7.1
A facile and efficient synthesis of pyrrolesfrom readily available amino acids is described. The key step in the method is an aza-Wacker oxidative cyclization catalyzed by palladium(II)/Cu(OTf)2. A series of pyrroles were obtained by this method under mild conditions.
Identification of a Valuable Kinetic Process in Copper-Catalyzed Asymmetric Allylic Alkylation
作者:Jean-Baptiste Langlois、Alexandre Alexakis
DOI:10.1002/anie.201005373
日期:2011.2.18
Copper bottomed: The application of a previously described process of dynamic kineticasymmetric transformation to acyclic substrates allowed the identification of a relevant kineticprocess in the title reaction (see scheme; CuTC= copper(I) thiophencarboxylate, Naphth= naphthyl). The optimization of the reaction conditions and generality of the method, as well as mechanistic considerations are disclosed
We report the first synthesis of the two components of the female sexpheromone of Matsucoccus josephi (2E,4E,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (1) and (2E,4Z,8E)-4,6-dimethyl-2,4,8-decatrien-7-one (2) utilizing the Reformatzky and Wittigreactions as key steps. A mixture of 1 and 2 and the separate isomers were bioassayed in a pine forest indicating that E isomer 1 is much more active than 2