10 - Synthesis of functionalized pyrrole and indole derivatives through carbometallation of lithiated double bonds

JAVIER F. FAÑANÁS; ALEJANDRO M. GRANADOS; ROBERTO SANZ; J.M. IGNACIO; JOSÉ BARLUENGA

CHEMISTRY-A EUROPEAN JOURNAL

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2001 vol. 7 p. 2896 - 2907

0947-6539

Bis(2-lithioallyl)amines derived from bis(2-bromoallyl)amines undergo intramolecular carbometallation of a lithiated double bond, giving dilithiated dihydropyrroles. The cyclizations are promoted by N,N,N′,N′-tetramethylethylenediamine (TMEDA). Reaction of these intermediates with electrophiles allows the preparation of some new fused and nonfused five-membered functionalized heterocycles. Although 2-lithioallylamines do not suffer intermolecular carbometallation, dimerization products are obtained with their copper or zirconium derivatives. Finally, the application of this new reaction to 2-lithio-N-(2-lithioallyl)anilines leads to 3-lithiomethylindole derivatives, which are transformed to functionalized indole derivatives by reaction with electrophiles.