Kabachnik-Fields reactions with stable nitroxide free radicals

The Kabachnik-Fields reaction is a multicomponent reaction that provides alpha-aminophosphonates and phosphorus analogs of alpha-amino acids. While paramagnetic alpha- amino acids are well known, to the best of our knowledge, this is the first report on paramagnetic.-aminophosphonate syntheses. We present examples of nitroxide-containing.-aminophosphonates starting from five- and six-membered paramagnetic aldehydes, a paramagnetic ketone, and five- and six-membered paramagnetic amines. Starting from a beta-bromo-alpha,beta unsaturated aldehyde, we constructed a pyrroline-nitroxide-condensed heterocycle with a phosphonate ester substituent. [GRAPHICS]