On the amination of 1,2,4-triazines by potassium amide in liquid ammonia and by phenyl phosphorodiamidate. A 15n-study |
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Authors: | A Rykowski H C Van Der Plas |
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Abstract: | The amination of 5-R- and 6-R-3-X-1,2,4-triazines (R = C6H5, t-C4H9, X = SCH3, SO2CH3, N+ (CH3)3, Cl) by potassium amide in liquid ammonia has been studied. In all reactions the formation of the corresponding 3-amino-1,2,4-triazines takes place; in some reactions by-products were found: from 5-phenyl- and 5-t-butyl-3-(methylthio)-1,2,4-triazine a ring contracted product i.e. 5-phenyl and 5-t-butyl-3-(methylthio)-1,2,4-triazole, from 6-phenyl-3-(methylthio)-1,2,4-triazine the dimer 3,3′-bis-(methylthio)-6,6′-bisphenyl-5,5′-bi-1,2,4-triazine and from 5-t-butyl-3-(trimethylammonio)-1,2,4-triazine chloride compound bis-(5-t-butyl-1,2,4-triazin-3-yl)- amine. Furthermore the conversion of 5-phenyl- and 5-t-butyl-1,2,4-triazin-3-one into the corresponding 3-amino compound by treatment with phenyl phosphorodiamidate (PPDA) was studied. A 15N study of these aminations showed that nearly all compounds undergo substitution according to both SN(AE) and SN(ANRORC) processes. The contribution of each of the competitive mechanisms to the amination is strongly influenced by the character of the leaving group. |
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