RESUMO
A palladium(ii)-catalyzed vicinal as well as geminal selective dicarbofunctionalization of allylamine embedded in a removable picolinamide auxiliary is developed by exploiting a nucleopalladation-triggered intermolecular three-component coupling reaction. The vicinal selectivity was accomplished by engaging allylamine, indoles, and aryl or styrenyl halides through a Pd(ii)/Pd(iv) reaction manifold, while the two-fold coupling of allylamine and indoles via a Pd(ii)/Pd(0) reaction modality resulted in geminal selectivity. The protocol is operationally simple, scalable, and offers two distinct types of products bearing functionalized tryptamine and bisindolyl frameworks in very high to excellent yields. The reaction features a wide substrate generality and also remains effective in the presence of various medicinally relevant scaffolds. Notably, this work represents the first example of nucleopalladation-guided intermolecular dicarbofunctionalization of allylamines.
RESUMO
A regio- and stereoselective allylation of N-unsubstituted anilines has been developed that explores aryl allenes as masked allyl synthons and a combination of Mg(OTf)2/HFIP as an effective proton source. The protocol is operationally simple and scalable and offers high yields of diverse p-allyl anilines bearing an olefin motif with exclusive E-geometry. The methodology was also suitable for the regioselective allylation of indole and can be advanced in a three-component reaction mode using NIS activator. The alteration of the catalytic system with TfOH resulted in the regioselective difunctionalization of allenes, which follows an allylation/hydroarylation cascade.