The direct preparation of the esters of p-nitrobenzylphosphonic acid from p-nitrobenzyl halides

✍ Scribed by Dariusz Witt; Janusz Rachon

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 602 KB
• Volume: 7
• Category: Article
• ISSN: 1042-7163
• DOI: 10.1002/(sici)1098-1071(199610)7:5<359::aid-hc12>3.0.co;2-p

✦ Synopsis

The reaction of sodium diisopropyl phosphite with p-nitrobenzvl bromide was studied in detail by ( 1 ) isolation and identification of all products and (2) studying the effects of radical traps, such as dicycbhexylphosphine, di-tert-butylnitroxide, and the diisopropyl phosphite anion, on product distribution. The results of the experiments cam'ed out are compatible with a proposed X-philic substitutiodSETtandem mechanism. It was demonstrated that p-nitrobenzyl chloride is also a good single-electron acceptor from the p-nitrobenzyl anion. The anion radical derived from p-nitrobenzyl chloride decomposes into the p-nitrobenzyl radical, which couples with an appropriate anion if it is present in a high enough concentration in the reaction mixture, to produce the dimer or the pnitrobenzylphosphonate.