Synthesis and Structural Characterization of Half-Sandwich Arene–Ruthenium(II) Complexes with Bis(imidazol-1-yl)methane, Imidazole and Benzimidazole
Round 1
Reviewer 1 Report
This very interesting manuscript reports the synthesis, full characterization, and crystal structures of a new series of half-sandwich
arene-ruthenium(II) coordination compounds derived from bis(imidazol-1-yl)methane, imidazole and benzimidazole.
The results obtained in the present work are clearly of very high scientific significance with a considerable potential to be explored in further research while searching for applications of such compounds in, for example, catalysis or as bioactive molecules. This manuscript extends the authors' well-known prior research on this topic and is excellently organized and presented, technically correct and supported by detailed data. The subject of this study is of high importance and contributes to widening the family of organometallic Ru complexes.
By providing an attractive blend of inorganic and organometallic chemistry, this work also well fits the scope of Inorganics. I therefore highly recommend the publication of this manuscript.
A few minor points can be addressed in a revised version.
1. Please check if all abbreviations are explained.
2. Formulae/numbers of compounds 1-3 can be mentioned in the abstract.
3. A number of recent references (last five years) cited is not high. The authors are advised to refer some more recent studies on the topic in the introduction.
4. Please check if graphical abstract is supplied (not available to this reviewer).
Author Response
1. Please check if all abbreviations are explained.
All abbreviations are explained.
2. Formulae/numbers of compounds 1-3 can be mentioned in the abstract.
Compound numbers were added to their formulae in the abstract.
3. A number of recent references (last five years) cited is not high. The authors are advised to refer some more recent studies on the topic in the introduction.
The reference list for the introduction part was updated (refs. 1-6) and now includes works from 2018-2021.
4. Please check if graphical abstract is supplied (not available to this reviewer).
The graphical abstract was uploaded through the submission system.
Reviewer 2 Report
Potapov and coworkers reported report the synthesis of mono- and binuclear arene-ruthenium(II) complexes with imidazole ligands by the reaction of the ligands with [(p-cym)Ru(μ-Cl)2]2 dimers. Unusual C-N bond breaking in bis(imidazol-1-yl)methane was observed in acetonitrile, leading the formation of the complex with imidazole. In methanol, a binuclear complex with two bridging bis(imidazol-1-yl)methane ligands was obtained. All ligands and ruthenium complexes were characterized well and this work could be accepted.
Author Response
Thank you for a positive assessment of our work.
Reviewer 3 Report
The manuscript reports mono- and binuclear half-sandwich ruthenium(II) complexes with imidazole ligands and characterized with FT-IR, NMR, EA and single crystal X-ray diffraction methods to conform the molecular structures. It is interesting found that the mono and binuclear half-sandwich ruthenium(II) complexes with bis(imidazole-1-yl)methane ligand in different solvent, acetonitrile and methanol. The reason or mechanism should be investigated in details. The further experiment should be done in this work. And the application of obtained ruthenium complexes will be done in this work. It is better given the Ms of obtained complexes.
Author Response
1. The reason or mechanism should be investigated in details.
A possible pathway for the formation of complex 1 was rationalized based on NMR monitoring of the reaction, see lines 66-100.
2. The further experiment should be done in this work. And the application of obtained ruthenium complexes will be done in this work.
Catalytic activity in transfer hydrogenation and cytotoxicity against MCF-7 and HepG2 cells were evaluated for the complexes 1-3, sections 2.4 and 2.5 were added.
3. It is better given the Ms of obtained complexes.
The structures of the complexes were determined by single-crystal X-ray diffraction and their chemical and phase purity was confirmed by elemental and PXRD analyses, we believe this set of methods is adequate enough for the characterization of the complexes.
Round 2
Reviewer 3 Report
I recommend this work publication in the journal.