steric

Hyperconjugation not steric repulsion leads to the staggered s ...

而不是老教科提到阻效应。

As steric hindrance of the aryl amine decreased and nucleophilicity increased, occurrence of the transfor-mation reaction increased and herbicidal activity of the product decreased.

芳胺空间阻越小,亲核性越强,反应越容易发生,产物除草活性越低。