Free-amine-directed alkenylation of C(sp2)-H and cycloamination by palladium catalysis
A new protocol for the palladium-catalyzed free-amine-directed alkenylation of C(sp2)-H bonds and cycloamination is described. Substituted biaryl-2-amines react with various alkenes, including electron-deficient alkenes, aryl alkenes and alkyl alkenes, to give the corresponding phenanthridines with exclusive regioselectivity. The use of α-branched styrenes leads to the formation of tricyclic compounds with a seven-membered amine ring. The method operates through a free-amine-directed alkenylation and a subsequent hydroamination cyclization reaction. Seven-membered cycloamination: A new protocol for the palladium-catalyzed free-amine-directed alkenylation of C(sp2)-H bonds and subsequent cycloamination is described (see scheme). Substituted biaryl-2-amines react with various alkenes to give the corresponding phenanthridines with exclusive regioselectivity. The use of α-branched styrenes leads to the formation of tricyclic compounds with a seven-membered amine ring. Copyright