Intermolecular defluorinative 1,2-diamination of fluoroalkenyl iodides with sulfonamides: synthesis of acyclic and cyclic fluorinated 1,2-enediamines

Alkene diamination represents one of the most straightforward strategies for 1,2-diamine derivatives synthesis. However, transition-metal-free 1,2-diamination of fluoroalkenes has been less studied. Here we report an intermolecular defluorinative vicinal diamination protocol employing easily prepared fluoroalkenyl iodides and sulfonamides for the efficient synthesis of a series of fluoroalkenyl-containing acyclic and cyclic 1,2-enediamines. The multiple halogen atoms (one iodine atom and two fluorine atoms) present on functionalized fluoroalkenes function as detachable “activators”, facilitating C-N bond formation under conditions that are devoid of transition metals, electricity, and photoirradiation. This method overcomes the need for additional oxidants required by traditional methods and exhibits good functional group tolerance and excellent scalability. The synthetic versatility is also demonstrated in the late-stage modification of biologically active molecules.