REGIOSELECTIVITY OF NUCLEOPHILIC ATTACK IN THE REACTIONS OF 1,2,4-TRIAZINE 4-OXIDES WITH CERTAIN C-NUCLEOPHILES
Keywords:
1,3-diketones, organomagnesium compounds, 1,2,4-triazine, nucleophilic substitution of hydrogenAbstract
The addition of CH-active compounds to 6-aryl-1,2,4-triazine 4-oxide is reversible and occurs under conditions of kinetic control at position 5 of the heterocycle to form cyclic C(5)-σH adducts. Under conditions of thermodynamic control the nucleophilic attack is directed to position 3 of the heterocycle and is accompanied by its opening to form the more stable open chain addition products. Attack of ethylmagnesium bromide is directed exclusively to the 5 position of the 6-aryl-1,2,4-triazine 4-oxides as a result of the irreversibility of the given reaction.
How to Cite
Kozhevnikov, D. N.; Prokhorov, A. M.; Rusinov, V. L.; Chupakhin, O. N. Chem. Heterocycl. Compd. 2004, 40, 911. [Khim. Geterotsikl. Soedin. 2004, 1060.]
For this article in the English edition, see DOI https://doi.org/10.1023/B:COHC.0000044574.23114.58