Regioselectivity in Reactions of Bis-Hydrazonoyl Halides with Some Bifunctional Heterocycles
作者:Ahmad S. Shawali、Magda A. Abdallah、Mohie E. M. Zayed
DOI:10.1002/jccs.200200148
日期:2002.12
chloride 1 reacts regioselectively with 3-mercapto-1,2,4-triazole 2a, 2,3-dihydro-3-thioxo-1,2,4-triazin-5(4H)-one 2b and 2-mercaptobenzimidazole 2c to give the hitherto unknown annelated 2,3-bis-(phenylhydrazono)thiazoles 6a-c, respectively. Reactions of 1 with the methylthio derivatives of such heterocycles afforded the annelated 3,3′-bis-(1,2,4-triazoles) 11a-c, respectively. Similar reaction of 1 with
Synthesis of bis(amidoxime)s and evaluation of their properties as uranyl-complexing agents
作者:Jérémy Stemper、Wei Tuo、Eva Mazarío、Ahmed S. Helal、Alexandre Djurovic、Claude Lion、Jean-Michel El Hage Chahine、François Maurel、Miryana Hémadi、Thierry Le Gall
DOI:10.1016/j.tet.2018.04.016
日期:2018.5
cations efficiently. To this end, various bis(amidoxime)s were synthesized by reaction of hydroxylamine with the corresponding dinitriles. In these compounds the amidoximes are separated by chains of various lengths, some including a heterocycle (pyridine or 1,3,5-triazine). The abilities of these bis(amidoxime)s to complex uranyl cation in water were evaluated by determining their affinity constants
Conjugate additions of non-nucleophilic N-containing compounds such as amides, thioamides, sulfonamides, and electron- poor anilines with different Michael acceptors can be promoted through the use of tributylphosphine. The range of useful pK(a)'s of nucleophiles has been established (pK(a)< 25) and new insights into the mechanism proposed. (c) 2007 Elsevier Ltd. All rights reserved.
Delaby et al., Comptes Rendus Hebdomadaires des Seances de l'Academie des Sciences, 1951, vol. 232, p. 1851