RESUMO
A new synthetic method to access α-nitroso pyrroles is presented. This method utilises the nitrosonium salt NOBF4, enabling short reaction times (<10 minutes) and avoiding the harsh acidic conditions usually associated with pyrrole nitrosation. Application of this procedure to diarylated pyrroles yielded several novel nitroso-pyrroles. Modifications to the method, through exclusion of air and inclusion of a mild base, allowed for the nitrosation of pyrroles bearing aryl groups substituted with electron-donating groups. Attempts to nitrosylate pyrroles bearing alkyl substituents resulted in the formation of a dimeric material composed of a pyrrolic unit and a 2-hydroxyimino-protected 1,5-dihydro-2H-pyrrol-2-one.
RESUMO
The synthesis of naphthylarylethanes via the photodecarboxylation of naphthylmethyl arylacetate esters is reported where the aryl group is able to stabilize a charge transfer reaction. The reaction proceeds via intramolecular charge transfer from the donor to acceptor, thereby enhancing a pathway to produce, within the solvent cage, the desired diarylethane products. These in-cage naphthylarylethanes are produced in good yields, in a single photochemical step, with the use of cyclohexane as a solvent providing optimal yields.