Copper-Catalyzed Cross-Coupling Between (E)-1,2-Diiodoethene and Carbazates: Entry to β-Functionalized N-Alkenylcarbazates

Aims: This work aims to widen the scope of methodologies to prepare functionalized N-alkenylcarbazates. Background: Alkenylcarbazates are generally prepared via Aza-Baylis-Hillman reactions, nucleophilic attack on ketones or a tandem carbometallation/amidation reaction of alkynes. Objective: The objective of this work is to develop a method to prepare functionalized N-alkenylcarbazates that alleviates the problem encountered in the above methods (use of electron deficient alkenes, use of stoiechiometric amounts of metal, access to symmetrical dicarbazates only). Methods: Use of copper-catalyzed cross-coupling between vinylic diiodide and carbazates to prepare functionalized N-alkenylcarbazates. Results: Various beta-iodovinylcarbazates were synthesized with up to good yields. The highest yields were obtained using dicarbazates. Functionalization of beta-iodovinylcarbazate demonstrated that the vinyl iodide moiety of these molecules can be substituted by a variety of functional groups via transition metal-catalyzed coupling reactions. Conclusion: Copper-catalyzed cross-coupling reaction is efficient to prepare functionalized N-alkenylcarbazates.