Disubstituted tetrahydroisoquinolines are prepared in one step from Michael acceptors and 2phenylethylamines under Pd catalysis and Ag 2 CO 3 as an oxidant. Presumably, activation of an ortho C−H bond of the aromatic ring with Pd(II) is directed by the primary amine to form a palladacycle. Insertion of the olefin, subsequent conjugated addition of the amine, and reductive elimination of Pd(0) affords the expected products. Silver carbonate is not necessary when 2-phenylethylamines are converted previously to N-benzoyloxy-2-phenylethylamines.

Using simplified model derivatives, the assembly of the macrocyclic rings of madangamines, including the 13-and 14-membered D rings of madangamines C-E, the all-cis-triunsaturated 15-membered D ring of madangamine A, and the (Z,Z)-unsaturated 11-membered E ring common to madangamines A-E, has been studied.The marine sponges belonging to the order Haplosclerida are a source of numerous polycyclic alkaloids with a variety of skeletal structures (manzamines, sarains, nakadomarin A, ingenamines, madangamines, among others), which share a common biogenetic origin from oligomeric macrocycles bearing a partially reduced 3-alkylpyridine moiety. 1 In particular, madangamines (Figure 1) possess an unprecedented diazatricyclic core (rings A-C) and two macrocyclic rings connecting N-7 with C-9 (ring D) and N-1 with C-3 (ring E). 2 Although significant in vitro cytotoxicity against a number of cancer cell lines has been

A new method for the preparation of 2,2-disubstituted indolines from 2-phenylethylamines was developed under Pd catalysis and PhI(OAc) 2 as oxidant. Imines derived from 2-pyridinecarboxaldehyde were formed in situ to direct a C-H activation process. The resulting imines were also oxidized to the corresponding amides in the same Pd-catalyzed process to obtain the final indoline as a picolinamide.