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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.

A facile protocol for the tunable synthesis of 10-hydroxy-1-azaspiro[4.5]deca-3,6,8-trien-2-ones and benzo[ b ]pyrrolo[2,1- c ][1,4]oxazin-3-ones is described. A tunable synthesis has been realized by the use of ZnBr 2 /oxone and tetra- n -butylammonium bromide (TBAB)/oxone. The reaction proceeds smoothly with high efficiency and a broad substrate scope. Mechanistic studies indicate that an N -protecting group-assisted ortho-trapping reaction is involved. In the transformation, the reaction undergoes α-addition, ipso -cyclization, and ortho-trapping of the resulting spirocyclic species.