123313-07-5Relevant articles and documents
Electrochemical versus anionic oxygenation of azathymine derivatives
Butora, Gabor,Reed, Josephine W.,Hudlicky, Tomas,Brammer Jr., Larry E.,Higgs, Paul I.,Simmons, Dana P.,Heard, Nina E.
, p. 7694 - 7701 (1997)
Pymetrozine (1) was converted to hemiaminal 2 in low to moderate yield by trapping its dianion with oxygen followed by reduction with ferrous salts. Pymetrozines 18 and 19 failed to undergo this type of oxygenation. All three pymetrozines were oxidized electrochemically at C5 to methyl hemiaminals 20, 21, and 22, respectively. Hydrolysis of 20 to 2 was accomplished under either acid- or base-catalyzed conditions in excellent yields, whereas the hydrolysis of methyl hemiaminals 21 and 22 was best performed under basic conditions. Soil metabolites of pymetrozine 1, hemiaminals 2 and 3, were prepared on a medium scale and in excellent yields. Linear sweep voltammetry data and conditions for preparative-scale electrochemistry are furnished for the precursory pymetrozines. Complete experimental and spectral data are provided for all new compounds, and the relative merits of anionic versus electrochemical oxidations for alkyl amides are discussed. A cautionary note is provided with the description of the conditions for large-scale anionic oxygenation because of potential explosive hazards.