Pan Xian-hua
2013
Citations
0
Influential Citations
1
Citations
Journal
Fine chemicals
Abstract
Ticagrelor,which is a small molecule anti-clotting drug peros with high selectivity,has anti-platelet activity without metabolic activation.And(1R,2S)-2-(3,4-difluorophenyl) cyclopropanamine is an important intermediate of ticagrelor.The key-step of Corey-Chaykovsky asymmetric cyclopropanation reactions was studied based on the references and the optimum synthetic conditions were developed as follows:L-menthol as chiral auxiliary agents;trimethylsulfonium iodide as sulfur-ylide reagent;n(DMSO):n(THF)=4:1 as reaction solvent;reaction temperature 10-12 ℃;and 10% CuI as reaction catalyst.Under such optimum conditions,the yield was 60.5%.Based on the reaction,the total yield of the five steps was 20.0%.