Approaches towards the synthesis of 7-halo-1,2-dihydroxyindolizidines (7-halolentiginosines) thwarting Grob fragmentation processes
作者:Carolina Vurchio、Franca M. Cordero、Cristina Faggi、Beatrice Macchi、Caterina Frezza、Sandro Grelli、Alberto Brandi
DOI:10.1016/j.tet.2015.03.108
日期:2015.9
The synthesis of 7-halo-1,2-dihydroxyindolizidines (7-halolentiginosines) starting from suitable protected 1,2,7-trihydroxyindolizidines (7-hydroxylentiginosines) has been studied. The results indicate a high propensity of the substrates to undergo fragmentation processes under standard halogenations conditions. The analysis of the products allowed an unprecedented full rationalization of Grob fragmentations