A novel regio- and stereospecific hydrohalogenation reaction of 2-propynoic acid and its derivatives
作者:Shengming Ma、Xiyan Lu、Zhigang Li
DOI:10.1021/jo00028a055
日期:1992.1
2-Propynoic acid and its derivatives are hydrohalogenated regio- and stereospecifically by reaction with lithium halides in acetic acid, or preferably with 1 equiv of acetic acid in refluxing CH3CN, to afford the thermodynamically unfavorable (Z)-3-halopropenoic acids and their derivatives as sole products. A rationale for the regio- and stereospecificity is briefly discussed.
Differentiation of the reactivities of carbon-carbon multiple bonds in one molecule. Highly chemo- and stereo-selective hydrohalogenation of allyl or propargyl propiolates
作者:Shengming Ma、Xiyan Lu
DOI:10.1016/s0040-4039(00)97323-4
日期:1990.1
The reaction of allyl or propargyl propiolates with lithium halides in acetic acid afforded allyl or propargyl (Z)-3-halopropenoates highly chemo- and stereo-selectively by differentiation of reactivities of carbon-carbon multiple bonds in the same molecule.
MA, SHENGMING;LU, XIYAN, TETRAHEDRON LETT., 31,(1990) N2, C. 7653-7656
作者:MA, SHENGMING、LU, XIYAN
DOI:——
日期:——
Mild Stereoselective Hydrohalogenation
Leading to (<i>Z</i>)-Halopropenamides at Room
Temperature
Hydroiodination of 2-propynamides leading stereoselectively to (Z)-iodopropenamides was achieved under mild conditions at room temperature by the combined use of zinc iodide and tertbutyl iodide. Similarly, the use of zinc bromide in the presence of tert-butyl bromide enabled the synthesis of (Z)-bromopropenamides. (Z)-Halopropenoic esters were also prepared in high yields.