Palladium-Catalyzed Cycloaddition of Alkynylimines, Double Isocyanides, and H2O/KOAc
Dianpeng Chen1, Min Yang2, Jianming Li1
1Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China.
Abstract:
In this work, a palladium-catalyzed cyclization of alkynylimines and double isocyanides is described. This facile procedure is efficient for synthesizing various 4-amidyl-2-aminopyrroles. Mechanism investigation indicates that a four-membered ring-fused pyrrole species is a key intermediate and the reaction involves [4 + 1] cycloaddition, protonation, nucleophilic addition, 1,4-addition of isocyanide, and rearomatization. Interestingly, the linear dipyrrole derivative is found to be an appropriate fluoride ion probe with a remarkable emission change, which could serve as a potential candidate for optoelectronic conjugated materials.
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