Sterical Driving Minor Actinide Selectivity of Bi-pyridyl Diamides: Ortho- vs. Para-Substitution
, Tsagana B. Sumyanova 1, Alexey V. Ivanov 1, Anastasia V. Kharcheva 1,2, Petr I. Matveev 1, Svetlana V. Patsaeva 2 and Vladimir G. Petrov 1,*Round 1
Reviewer 1 Report
The authors synthesized a new tetradentate ligand for the selective isolation of americium(III) from highly reactive wastes and showed the effect of the third substituent on photophysical properties, cation binding constants, and extraction properties. The research topic is important, the characterizations are well performed, the language is well written. The review has found that the same group had reported some similar ligands without the third methyl group. Since the authors claimed some effects of the introduction of a third substituent in the aryl fragment, it would be better to compare their performance under similar conditions.
Author Response
Thank you for your comments!
Regarding this point: "The review has found that the same group had reported some similar ligands without the third methyl group. Since the authors claimed some effects of the introduction of a third substituent in the aryl fragment, it would be better to compare their performance under similar conditions."
In the text of the manuscript we have allready discussed dimethyl substitued ligands in part of:
a) complexation studies:
"It was also found that the stability constants of complexes of cerium and europium nitrates with 2,4,5-triMe diamide are higher than those of unsubstituted anilide. When comparing the stability constants of complexes for dysprosium nitrate with trimethyl-substituted, unsubstituted, and 2,4-dimethyl-substituted anilides. "It was established that the stability values of complexes with unsubstituted and 2,4,5-triMe diamides are within the confidence interval and are an order of magnitude higher than the stability constant of the complex with 2,5-diMe diamide. Also comparing the constants for the diphosphate tetradentate ligands and 2,4,5–triMe, we note that under identical conditions the binding constants for Eu(III) are close."
Nevertheless we added in table 1 more ligand for general comparison of binding ability.
b) lumeniscent study: "The luminescence quantum yield of a europium complex in acetonitrile solution was very low compared to other europium complexes with ligands of similar structure[12–14]"
c) solvent extraction study:
"Comparing with earlier studies of extraction systems under identical conditions, the tri-substituted ligand has a higher extraction efficiency than the mono- and di-substituted ones[12,18]."
"It is interesting to note that the nature of this relationship indicates that this ligand is more similar to 2,5- than to 3,4- or even to 2,4-dimethyl-substituted aryls of bipyridn-di-carboxylic acid[12]. This indicates that positions 2 and 5 play a greater role than positions 3 and 4, which is most likely due to the steric factor[9]"
Reviewer 2 Report
Minor actinides contained in the high level radioactive waste have a half-life that reaches millions of years, causing economic and environmental problems. Reprocessing nuclear waste has become an important issue for developing nuclear energy. However, because of the similar properties of actinides and lanthanides, isolating minor actinides from the nuclear waste is very challenging. This paper presents a new ligand and conducted a series studies on this ligand and its complexes. It is interesting and well organized. The obtained results would be valuable for the study of nuclear waste reprocessing. Several typos are needed to be revised:
1. The abbreviation “NMR” should be specified.
2. “...of of the europium complex in solid state...”
3. “to the corresponding structures of well-known dimethylated dianilides In terms of photophysical properties”
4. “Complexes of 2,3,4–triMe diamide with La, Sm, Eu, Gd μ Tb”
Author Response
Thank you so much for your comments! We corrected the typos.
Reviewer 3 Report
I recommend the manuscript for publication in its current form.
Author Response
Thank you for your recommendation!
Round 2
Reviewer 1 Report
the reviewer suggest publish it in this journal as it is
Reviewer 2 Report
The comments have been well responsed by the revised paper, and it deserves publication.
