Ring-Opening 1,3-Halochalcogenation of Cyclopropane Dicarboxylates

Donor–acceptor
cyclopropanes with two geminal carboxylic
esters are reacted with chalcogenyl chlorides and bromides to afford
ring-opened products bearing the halogen atoms in the 1-position,
adjacent to the donor, and the chalcogenyl residue in the 3-position
next to the two acceptor groups. A variety of different donors (e.g.,
aryl, N, and O) are used. The stereospecificity of the reaction is
demonstrated by using a chiral starting material.

供体-受体型环丙烷，其分子中含有两个相邻的羧酸酯，通过与硫族氯化物和溴化物反应，可生成在1位含卤原子、紧邻供体，并在3位含硫族基团、紧邻两个受体基团处的开环产物。反应中使用了多种不同的供体（例如，芳基、N和O原子）。通过使用手性起始材料，反应的立体选择性得到了验证。