A novel skeletal rearrangement in the Ritterreaction was examined which conveniently generated p-menthane diamides from turpentine. A probable reaction mechanism was proposed based on employing thermodynamic analysis. All the products were purified and characterised by 1H NMR, IR, X-ray crystallography and ESI+-MS.
13C NMR spectral analyses, and their pre-emergence herbicidalactivities against ryegrass were evaluated. All of the compounds showed excellent herbicidalactivity. The Schiff bases showed stronger herbicidalactivities than the original amine 4. These compounds showed herbicidalactivities comparable to that of glyphosate. The herbicidalactivities of 5k and 5l against ryegrass shoot growth were 78
对p -Menth-3-en-1-amine 4及其Schiff碱衍生物5a - 1进行了设计和合成。通过FT-IR,ESI + -MS,HRMS,1 H NMR和13 C NMR光谱分析对其进行了表征,并评估了它们对黑麦草的芽前除草活性。所有化合物均表现出优异的除草活性。Schiff碱比原始胺4具有更强的除草活性。这些化合物显示出与草甘膦相当的除草活性。5k和5l的除草活性对抗黑麦草芽的生长分别比草甘膦高78.3%和355.6%。此外,向含呋喃或苯环的席夫碱衍生物中引入氯或溴原子有利于提高活性。然而,当五元杂环席夫碱的杂原子或吡啶席夫碱上的取代基的位置改变时,除草活性并未受到明显影响。