Abstract
The synthesis and the chemical, spectral and biological properties of N-phosphonylmethyl-and N-phosphinylmethyl-aminomalonic acids and derivatives, i.e. 0,0-dialkyl-N-di(alkoxycarbonyl)metnyl-N-benzylaminomethylphosphonates (1a-e), 0,0-dialkyl-N-di(alkoxycarbonyl)-methylaminomethyl-phosphonates (2a,2b), 0-isopropyl-N-di(hydroxycarbonyl)-methyl-aminomethylphosphonic acid trisodium salt (3), 0,0-bis(trimethylsilyl)-N-di(alkoxycarbonyl)methyl-N-benzyl-aminomethylphosphonates (4a-d), N-di(alkoxycarbonyl)-methyl-N-benzylaminomethylphosphonic acids (5a-c), N-di(alkoxycarbonyl)methyl-aminomethylphosphonic acids (6a-b), N-di (hydroxycarbonyl)methyl-aminomethylphosphonic acid (9), -tetrasodium salt (7) and -diisopropylamine salt (8), 0-ethyl-N-di (ethoxycarbonyl) methyl-N-benzylaminomethyl-methylphosphinate (10), 0-trimethylsilyl-N-di(ethoxycarbonyl) methyl-N-benzylaminomethyl-methylphosphinate (11). N-di(ethoxy-carbonyl)methyl-N-benzylaminomethyl-methylphosphinic acid (12) and N-di(ethoxycarbonyl)methyl-aminoethyl-methylphosphinic acid are reported. It is demonstrated that the formulated compound 6b has about the same herbicidal activity as Glyphosate 14, whereas 6a is somewhat weaker. When dissolved in pure water Glyphosate is herbicidally more active by a factor of 2 to 4 than 6a and 6b. It is shown that this difference in the herbicidal activity of 6a and 6b is due to the different stabilities of 6a and 6b in pure water and in water plus additives, respectively.