Abstract: In this article, We have measured the ³¹P chemical shifts of the title compounds and discussed the relationship of their chemical shift-electronic effect.
It is suggested that a correlation between ³¹P chemical shifts of various O-ethyl O-aryl N-isopropyl aminothionophosphates and their herbicidal activities can be set up as shown in the following empirical approaeh
PI₅₀=-0.9025π² +0.9017π -0.560E_s-
-0.1620ΔδP + 0.8445I+4.2514
n=28, R=0.9231, S=0.3959
Its approximation and discrepancy have been discussed.