A Tetranuclear Ni(II)-Cubane Cluster Molecule Build by Four µ3-O-Methanolate (MeO) Ligands, Externally Cohesive by Four Unprecedented Bridging µ2-N7,O6-Acyclovirate (acv-H) Anions
, Ricardo Navarrete-Casas 1, Antonio Frontera 3, Alfonso Castiñeiras 4, Juan Niclós-Gutiérrez 1 and Antonio Matilla-Hernández 1,*
Round 1
Reviewer 1 Report
This manuscript reports on synthesis and characterization of novel Ni complex with acyclovir. There are only few examples of complexes of such type and the manuscript is quite interesting. The work is well organized and presented. Nevertheless, there are some flaws that should be addressed before acceptance.
In abstract section:
1) lines 17-19: 'This contribution deals on molecular recognition between synthetic purine 17 nucleosides and first-row transition metal complexes, with O- and/or N-amino chelators able to 18 build intra-molecular N-H···(N or O), O-H···N or O-H···O) interligand interactions'
This sentence is inhomogenious. 'This contribution deals on molecular recognition between synthetic purine 17 nucleosides and first-row transition metal complexes, with O- and/or N-amino chelators able to 18 build intra-molecular N-H···(N or O) and O-H···(N or O) interligand interactions' seems to be more appropriate.
2) lines 21-22: 'A part of our continuous interest in diethylenetriamine (dien) or its analogues, where 21 one or two of N-dien donors are replaced by O(e)-ether or O(ol)-alcohol atoms' this goes beyond this manuscript and is better to be omitted.
In main text:
3) Line 55, abbreviation 'MBP' appears here for the first time (in main text) and should be explained.
4) Lines 149-158, DFT calculations have been performed for isolated molecule. Please, give the details on the molecular geometry optimization (relaxation).
Please, specify, is the Hessian calculations followed by frequencies analysis have been performed.
5) Figures 1-4 on the one hand and Figures 5-6 on the other hand used different atom coloring scheme. In particular, N atoms are depicted in green and blue colors respectively. This confuses the reader. In general, N atoms are usually depicted in blue color in most of crystallographic programs.
Please, synchronize the coloring scheme within the manuscript.
6) In order to confirm the identity of single crystalline and powder samples the Powder XRD analysis is strongly recommended.
Some typos:
Page 8, line 238, 'small red spheres in Figure 7)' should be 'small red spheres in Figure 6)'
Page 9, line 267, 'complexes whit octahedral' should be 'complexes with octahedral'
Author Response
This manuscript reports on synthesis and characterization of novel Ni complex with acyclovir. There are only few examples of complexes of such type and the manuscript is quite interesting. The work is well organized and presented. Nevertheless, there are some flaws that should be addressed before acceptance.
Reply: Thanks for the positive comments
In abstract section:
1) lines 17-19: 'This contribution deals on molecular recognition between synthetic purine 17 nucleosides and first-row transition metal complexes, with O- and/or N-amino chelators able to 18 build intra-molecular N-H···(N or O), O-H···N or O-H···O) interligand interactions'
This sentence is inhomogeneous. 'This contribution deals on molecular recognition between synthetic purine 17 nucleosides and first-row transition metal complexes, with O- and/or N-amino chelators able to 18 build intra-molecular N-H···(N or O) and O-H···(N or O) interligand interactions' seems to be more appropriate.
Reply: Done!
2) lines 21-22: 'A part of our continuous interest in diethylenetriamine (dien) or its analogues, where 21 one or two of N-dien donors are replaced by O(e)-ether or O(ol)-alcohol atoms' this goes beyond this manuscript and is better to be omitted.
Reply: Done!
In main text:
3) Line 55, abbreviation 'MBP' appears here for the first time (in main text) and should be explained. MPP appears for the first time in the Abstract. But we also clarify that in main text.
Reply: Done
4) Lines 149-158, DFT calculations have been performed for isolated molecule. Please, give the details on the molecular geometry optimization (relaxation). Please, specify, if the Hessian calculations followed by frequencies analysis have been performed.
Reply: The details regarding the optimization and Hessian calculations have been added in the theoretical methods (see lines 157 to 159)
5) Figures 1-4 on the one hand and Figures 5-6 on the other hand used different atom coloring scheme. In particular, N atoms are depicted in green and blue colors respectively. This confuses the reader. In general, N atoms are usually depicted in blue color in most of crystallographic programs.
Please, synchronize the coloring scheme within the manuscript.
Reply: Done, All structural figures have been created again according to the suggestion made.
6) In order to confirm the identity of single crystalline and powder samples the Powder XRD analysis is strongly recommended.
Reply: Thank you for this comment. Unfortunately, we cannot satisfy this recommendation because this would require running a new synthesis experience since we have not enough sample. However, it is clear that the observation of the crystals, like those shown in the photo at section S1 of Supplementary material, suggests that the sample is homogeneous and of excellent purity. As indicated in the synthetic procedure in section 2.2 of the main-text, the synthesis requires controlling a very slow evaporation of solvent (methanol) for no less than 2 months (covering the crystallizer with a plastic film) and totally unperturbed. Therefore we would need at least 2 months to get enough sample to do the Powder XRD analysis
Some typos:
Page 8, line 238, 'small red spheres in Figure 7)' should be 'small red spheres in Figure 6)'.
Reply: Fixed
Page 9, line 267, 'complexes whit octahedral' should be 'complexes with octahedral'
Reply: Fixed
Reviewer 2 Report
In this manuscript, Belmont-Sánchez et al. present preparation of novel Ni(II) cubane-type complex with acyclovir-derived ligands. Overall, this structural type of complexes is well known, but addition of another representative is worth being published. Apart of XRD, the authors present IR and UV-Vis data, as well as thermal stability of the compound.
Scientifically, the work is of interest for specialists in coordination chemistry. It can be published almost as it is. My only recommendation is to re-read the rext in order to improve the style and eliminate some typos.
Author Response
In this manuscript, Belmont-Sánchez et al. present preparation of novel Ni(II) cubane-type complex with acyclovir-derived ligands. Overall, this structural type of complexes is well known, but addition of another representative is worth being published. Apart of XRD, the authors present IR and UV-Vis data, as well as thermal stability of the compound.
Reply: Thank you for these positive comments
Scientifically, the work is of interest for specialists in coordination chemistry. It can be published almost as it is. My only recommendation is to re-read the text in order to improve the style and eliminate some typos.
Reply: Done!
