4-lithiosydnone imines: Generation and stability. Plant growth regulating activity of 4-hydroxymethyl derivatives of sydnone imines

Abstract

The C(4)-deprotonation of N6-substituted sydnone imines with lithium hexamethyldisilazide (LHDMS), lithium diisopropylamide (LDA), lithium diethylamide (LDEA), and n-BuLi was studied. A thermal stability of 4-lithiosydnone imines was investigated and an efficiency of subsequent reactions of the generated C(4)-lithio derivatives with electrophiles was shown to depend on the exploited deprotonating reagent. It was found that 4-(α-arylhydroxymethyl)sydnone imines, when used for pre-sowing treatment of corn seeds at very low doses (0.25-5 g t−1), promoted a plant growth up to 60%.