Palladium-Templated Regio- and Stereoselective Cyclization of 2'-Alkenyl 2-Alkynoates and Its Synthetic Applications
摘要:
2'-Alkenyl 2-alkynoates undergo facile stereoselective cyclization to alpha-(haloalkylidene)-gamma-butyrolactones upon treatment with a catalytic amount of palladium complex in the presence of CuX(2) and LiX. When an alkyl group is introduced to the 1'-position of the alkenyl group, unsubstituted 2-propynoates mainly give trans-beta, gamma-disubstituted gamma-lactones, and substituted 2-propynoates afford cis-beta,gamma-disubstituted gamma-lactones. Further elaborations of the halogen atoms and the synthesis of A-factor using this method are exemplified.
Palladium‐Catalyzed Oxidative Cyclization of Enynes with Hydrogen Peroxide as the Oxidant
作者:Guoyin Yin、Guosheng Liu
DOI:10.1002/anie.200801438
日期:2008.7.7
Palladium-Templated Regio- and Stereoselective Cyclization of 2'-Alkenyl 2-Alkynoates and Its Synthetic Applications
作者:Jianguo Ji、Chunming Zhang、Xiyan Lu
DOI:10.1021/jo00110a018
日期:1995.3
2'-Alkenyl 2-alkynoates undergo facile stereoselective cyclization to alpha-(haloalkylidene)-gamma-butyrolactones upon treatment with a catalytic amount of palladium complex in the presence of CuX(2) and LiX. When an alkyl group is introduced to the 1'-position of the alkenyl group, unsubstituted 2-propynoates mainly give trans-beta, gamma-disubstituted gamma-lactones, and substituted 2-propynoates afford cis-beta,gamma-disubstituted gamma-lactones. Further elaborations of the halogen atoms and the synthesis of A-factor using this method are exemplified.
Efficient Synthesis of α-Allylbutenolides from Allyl Ynoates via Tandem Ligand-Enabled Au(I) Catalysis and the Claisen Rearrangement
作者:Huiyan Wang、Ting Li、Zhitong Zheng、Liming Zhang
DOI:10.1021/acscatal.9b03501
日期:2019.11.1
A facile construction of α-allylbutenolides from readily available allyl ynoates has been developed viatandem gold-catalyzed alkyne isomerization to allene and cycloisomerization, the Claisen rearrangement and a double bond migration. The gold catalysis is enabled by a bifunctional phosphine ligand featuring a critical remote tertiary amino group, and the reaction tolerates a range of substituents