Photostimulated Intramolecular SRN1 Reactions with Nitrogen Nuclephiles: Synthesis of Fused Azaheterocycles

VICTORIA A. VAILLARD; MARÍA E. BUDÉN; SANDRA E. MARTÍN; ROBERTO A. ROSSI

Santiago de Compostela

Conferencia; 19 th IUPAC Conference on Physical Organic Chemistry; 2008

IUPAC

The radical nucleophilic substitution, or SRN1 reaction, is a chain process through wich an aromatic nucleophilic substitution is achieved. The initiation step is a electron transfer (ET) from suitable donors to the substrate to afford a radical anion. In some system, the ET step is spontaneus, however, in others light can initiate the reaction. Several nucleophiles such as carbanions and heteroatom anions can be used for SRN1 reactions to form a new C-C or C-heteroatom bonds in good yields. An exception to this case is the intermolecular reaction of aromatic amide ions with aromatic substrate. In this case, the formation of both, C-N and C-N bonds were observed. For instance, 2-naphtylamide ions reacted under irradiation with ArI, and 1-aryl-2-naphtylamines were formed regioselectively in 45-63% yield, with 3-6% of N-arylation.When a substrate has both, the leaving group ande the nucleophilic center, the intramolecular reaction affords a cyclic producto. Here we will report the intramolecular arylation of aromatic amide ions with a pendant aryl moiety with a suitable leaving group, to obtain fused azaheterocycles.