Sheehy, Kevin J.; Bateman, Lorraine M.; Flosbach, Niko T.; Breugst, Martin; Byrne, Peter A. published the artcile< Identification of N- or O-Alkylation of Aromatic Nitrogen Heterocycles and N-Oxides Using 1H-15N HMBC NMR Spectroscopy>, Recommanded Product: 3-(Methoxycarbonyl)pyridine, the main research area is aromatic nitrogen heterocycle oxide alkylation HMBC NMR.
A series of representative diazines and pyridine N-oxides were subjected to alkylation using several different alkylating agents. The 15N NMR chem. shifts (δN values) of the diazines, pyridine N-oxides and derived alkylation products were determined using 1H-15N HMBC NMR spectroscopy at natural 15N abundance. The changes in the 15N NMR chem. shifts (Δ(δN) values) that occurred on going from starting materials to products in these reactions were analyzed. N-alkylation of diazines resulted in large upfield shifts of the δN values of the alkylated nitrogen (of the order of 100 ppm or greater). While O-alkylation of pyridine N-oxides resulted in upfield shifts of the δN values of the N-(alkoxy)pyridinium nitrogen, the Δ(δN) values were of a much smaller magnitude (ca. -42 ppm) than those observed for N-alkylations of diazines. Nitrogen NMR spectroscopic data from the literature of relevance to alkylation of azines, diazines, azine N-oxides and diazine N-oxides was gathered together, and using this in tandem with our 15N NMR spectroscopic data, we have been able to corroborate our observations on the trends observed in the Δ(δN) values associated with N- and O-alkylation reactions of aromatic N-heterocycles and N-oxides. An anal. protocol that relies on synergistic evaluation of 1H-15N HMBC and 1H-13C HMBC NMR spectra has been developed that enables unambiguous diagnosis of the occurrence of N-alkylation of aromatic N-heterocycles and O-alkylation of aromatic N-oxides.
European Journal of Organic Chemistry published new progress about Alkylation. 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Recommanded Product: 3-(Methoxycarbonyl)pyridine.