Microwave-Assisted Tandem Nucleophilic Substitution-Wittig Reaction of α<i>-</i>Hypervalent Iodine Functionalized Phosphonium Ylide
作者:Xian Huang、Xiaochun Yu
DOI:10.1055/s-2002-34893
日期:——
Under microwave irradiation conditions the tandem nucleophilic substitution-Wittig reaction of α-hypervalent iodine functionalized phosphonium ylide can occur readily to afford α-heteroatom substituted-α,β-unsaturated enoates in good yields stereoselectively.
A Novel and Convenient Protocol for Synthesis of α-Haloacrylates
作者:Biao Jiang、Ying Dou、Xiangya Xu、Min Xu
DOI:10.1021/ol702859y
日期:2008.2.1
A.novel and convenient protocol for synthesis of alpha-haloacrylates starting from phosphonium ylide and aldedyde or alcohol was described. Halodimethylsulfonium halide was used for the first time in halogenation of phosphonium ylide. Good yield as well as a high Z/E ratio were shown in representative cases, and an umpolung dimethyl sulfide-ylide species might be involved as an intermediate.
New Synthetic Approach to α-Chlorocinnamates: First Example of Synthesis of Functionally Substituted Alkenes Using Catalytic Olefination Reaction
作者:Valentine G. Nenajdenko、Olesya N. Lenkova、Alexey V. Shastin、Elizabeth S. Balenkova
DOI:10.1055/s-2004-815951
日期:——
A new simple and efficient transformation of carbonyl compounds to α-chlorocinnamates is described. Catalytic olefinationreaction with ethyl trichloroacetate gives target alkenes in moderate to good yields. The reaction with aromatic aldehydes proceeds stereoselectively to form preferably Z-isomers.
A novel efficient and eco-friendly nanocrystallineZnO catalyst was used for the Knoevenagel condensation and for the reduction of CC double bonds at room temperature in the absence of solvents.