New synthetic technologies for the construction of heterocycles and tryptamines.

New synthetic methods for the construction of novel heterocycles and tryptamines are described. Thus, N-Boc anilines (I) are sequentially converted to heterocycles II ((3-(2-aminophenyl)pyrrolidin-3-ol) derivatives), III (substituted 2-oxo-1,2-dihydrospirobenzo[d][1,3]oxazine-4,3'-pyrrolidines), and VI (2-(4,5-dihydro-1H-pyrrol-3-yl)aniline) derivatives through a route involving t-BuLi induced ortho-metalation/LaCl(3).2LiCl metal exchange, reaction with N-Boc pyrrolidin-3-one (5), and subsequent decarboxylative fragmentation.

Sequential Rh(I)/Pd-catalyzed 1,4-addition/intramolecular allylation: stereocontrolled construction of gamma-butyrolactones and cyclopropanes.

The rhodium-catalyzed conjugate addition of functionalized vinyltin reagents to alkylidene Meldrum's acids, followed by Pd-catalyzed intramolecular allylation, is a direct entry into vinyl-substituted gamma-lactones via O-alkylation and vinylcyclopropanes via C-alkylation.

Palladium-catalyzed carbon-carbon bond-forming 1,2-ligand migration of organoalanes.

A one-pot, two-step process that transforms terminal alkynes into ethyl methyl-substituted benzylic quaternary carbon centers is described. (E)-2,2-Disubstituted-1-alkenyldimethylalanes have been shown to participate in 1,2-alkyl migration from aluminum to carbon with concomitant arylation at the 2-position to furnish ethyl methyl-substituted benzylic quaternary carbon centers, when reacted intramolecularly with aryl halides and triflates in the presence of a Pd(0) catalyst. The protocol is initiated with Cp2ZrCl2-catalyzed methylalumination of terminal alkynes followed by palladium-catalyzed intramolecular arylation of the resulting (E)-2,2-disubstituted-1-alkenyldimethylalanes, leading to 1,2-methyl shift from aluminum to carbon.