3847-19-6Relevant articles and documents
Ring-Centered Heterocyclic Cations and the Direct Heteroarylation of Aromatic and Heterocyclic Compounds
Song, Fenhong,St. Hilaire, Valentine R.,White, Emil H.
, p. 1957 - 1959 (2008/02/11)
(matrix presented) The protonation of heterocyclic diazotates (attachment adjacent to a nitrogen atom) yields ring-centered heterocyclic carbocations that are highly reactive. The carbocations were found to alkylate aromatic and heterocyclic compounds, such as benzene, N-methylpyrrole, and 2-aminopyridine, in reactions that are synthetically useful. This carbocation involvement may serve as a paradigm for the cross-linking of DNA by nitrous acid and the anticancer activity of heterocyclic diazotates.
Utilizing Acetyl Hypofluorite for Chlorination, Bromination, and Etherification of the Pyridine System
Hebel, David,Rozen, Shlomo
, p. 6298 - 6301 (2007/10/02)
Acetyl hypofluorite, which is easily made from F2, possesses a strong electrophilic fluorine.This electrophile is able to attach itself to the nitrogen atom of pyridine and activate the ring toward nucleophilic attacks.The ultimate elimination of HF results in an overall easy nucleophilic displacement of the hydrogen of the important 2-position .The nucleophiles used: Clδ-, Brδ-, ROδ-, originate from solvents such as CH2Cl2, CH2Br2, and various primary alcohols.Thus, 2-halo- or 2-alkoxypyridines were formed.The reaction conditions (room temperature, very short reaction times, and good yields) transform the task of direct substitution of the pyridine ring from an extremely difficult to a very easy procedure.