N-Deoxygenation

Ethyl 4-oxo-1,4-dihydro-l,7-naphthyridine-3-carboxylate 6-oxide underwent N-deoxygenation to give the 4-oxo-l,4-dihydro-l,7-naphthyridine-3-... 

The reaction of 1-nitronaphthalene and other bicyclic nitroarenes, for instance, 5-nitroquinoline, with dimethyl phosphite in methanol in the presence of sodium methoxide proceeds via formation of the corresponding o adducts with the phosphite anion, which are converted into substituted nitrosoarenes. Subsequent N-deoxygenation results in the formation of nitrenes that react further to give benzazepines and analogues (Scheme 20) [88]. 

Alkoxy-3-halopyridine-l-ox-ide, N-deoxygenated, 725 4-Alkoxy-3-halopyridine-l-ox-ides, from 3-halo-4-nitro-pyridine-l-oxides, 688 4-Alkoxy-3-halopyridines, from... 

Oxidation of llb(5 /2/iS) with excess MCPBA gave the diastereomeric sulfones 17 (39%) and sulfone 1-N-oxides 19 (51%) that were separated by silica gel chromatography. Deprotection of 17 or 19 gave the corresponding 5 -deoxy-5 -fluoro-5 -[(4-methoxyphenyl)sulfonyl]adenosines (18) or 1-N-oxides (20). Fractional crystallization of 20 (MeOH) gave 5 -deoxy-5 (S)-fluoro-5 -[(4-methoxyphenyl)sulfonyl]adenosine-l-N-oxide [20(5 5)] with I F NMR 5 -192.85 (dd, Vf-s = 45.0 Hz, = 28.5 Hz, F(5 S)]. Hexachlorodisilane effected smooth 1-N-deoxygenation of 19 to give 17. 

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