Copper-Based Metal–Organic Frameworks (MOFs) as an Emerging Catalytic Framework for Click Chemistry
, Gurleen Singh 1, Nancy George 1, Gurjaspreet Singh 2, Sofia Gupta 2, Harminder Singh 1, Gurpreet Kaur 3,* and Jandeep Singh 1,*
Round 1
Reviewer 1 Report
Please see the attachment
Comments for author File: 
Comments.pdf
Author Response
Dear Reviewer,
We are highly thankful to you for reviewing the manuscript and providing us your valuable suggestions and remarks for improvement of the manuscript. As per the suggestions received, the implementations have been carried out and the response for each query is given below:
All the changes have been highlighted as yellow text in the revised manuscript.
Reviewer
The authors have presented a review of recent developments on copper-based MOFs that
have been widely used for the condensation reaction, A3 coupling reaction (Amine, aldehyde
and alkyne), the synthesis of 1,2,3-triazoles and tetrazoles under a wide range of reaction
conditions. These catalysts have advantages such as improved yield, reduced reaction times
and efficient catalyst recovery. The mechanism for CuAAC using copper-based MOFs was
also discussed by others. Finally, the authors have also reviewed in a tabulated form various
parameter of Cu-MOs, namely MOF structure, oxidation state, recyclability, reaction
conditions and yields of triazoles formed.
There are a number of points that I hope the authors can address:
Response: Authors are highly thankful for the valuable comments and suggestions by reviewer.
- Comment: The authors use the concept of click chemistry in the title and discuss reactions in dioxane solvent and at high temperature?
Response: This is an interesting question. Dioxane is a useful solvent for a variety of reactions due to its relatively high boiling point of 101℃ and its miscibility with water due to which its removal becomes easy after the reaction completion, thereby making it a considerable benign solvent for click reactions. As for the temperature, 55-60℃ is the optimum temperature range reported for cycloaddition reactions.
- Comment: The abstract is not adequate with the text of the manuscript and only discusses the part of the synthesis of 1,2,3-triazoles.
Response: As per the valuable recommendation, the abstract has been modified with the incorporation of methods of synthesis of MOFs and their properties are highlighted in the revised manuscript.
- Comment: Author should mention the years covered for the review.
Response: As per the valuable remarks, the years covered has been mentioned in the abstract and highlighted in the revised manuscript.
- Comment: all the different MOF catalysts present in table 2 have an oxidation degree i. it ispossible to mention this in the title and avoid having a column only for oxidation
Response: As per the valuable recommendation, the column for oxidation state has been removed from the revised manuscript.
- Comment: It is preferable that the authors report the amount of catalyst in Table 2 by mol% instead of mg, % or wt.
Response: As per the valuable suggestions, it is good to have a uniform pattern to report the amount of catalyst in mol% but in many research papers the amount of catalyst used is in the units of mol% or wt% or mg. From the literature, it was understood that the amount of catalyst loading is variable but the reporting of all catalytic amounts in mol% becomes too difficult since the molecular weight of all Cu-MOFs being reported here from literature are not quoted in research papers. Therefore, still considering your suggestion for better representation and interpretation of data, the table has been trifurcated into three sub-tables (table 5,6,7) on the basis of the amount of Cu-MOF being used for catalysis.
- Comment: It is preferable that the authors standardize the amount of catalyst reported in Table 2 by mol% instead of mg, % or wt.
Response: As per the valuable suggestions, it is good to have a uniform pattern to report the amount of catalyst in mol% but in many research papers the amount of catalyst used is in the units of mol% or wt% or mg. From the literature, it was understood that the amount of catalyst loading is variable but the reporting of all catalytic amounts in mol% becomes too difficult since the molecular weight of all Cu-MOFs being reported here from literature are not quoted in research papers. Therefore, still considering your suggestion for better representation and interpretation of data, the table has been trifurcated into three sub-tables (table 5,6,7) on the basis of the amount of Cu-MOF being used for catalysis.
- Comment: Table 2 summarizes the different Cu-MOF discussed in the review. However, there is no relationship between the abstracts of the articles and the type of Cu-MOF in
Table 2. In order to avoid consulting Table 2 for information about Cu-MOF, each
abstract should be accompanied by a figure reporting the type and catalytic amount
of Cu-MOF, yield.
Response: As per the valuable recommendation, table 2 has been dissolved and instead new tables (table 5,6,7) have been added for better representation and understanding. In addition to this, as per remarks, the reactions/figures along with suitable description have been added throughout the manuscript at appropriate sections. This also restrains the readers to repeatedly consult tables and instead provides complete information at a single location, thereby making it more reader friendly.
- Comment: It is preferable that the authors discuss the mechanism of the other reactions
(condensation reaction, A3 coupling reaction and synthesis of tetrazoles).
Response: As per the valuable recommendation, the mechanisms have been added with brief description in the section 7 (figure 6,7,8) and highlighted in the revised manuscript. - Comment: Please leave spaces between values and their units
Page 14 : 4h
Page 15 : 7h
Page 16 : 3h
Page 17: 30mg, 12h
Page 18 : 2h
Page 24 : 7h
Page 26 : 5wt% ; 4h ; 8h …………
Response: As per the remarks, the spaces between the values and their units are corrected throughout the revised manuscript and highlighted.
- Comment: Please rate the citation of previous review.
Example
Recent Advances in Cu-Based Metal–Organic Frameworks and Their Derivatives for
Battery Applications (https://doi.org/10.1021/acsaem.2c01405)
Applications of copper-based metal organic frameworks
(doi.org/10.1016/j.matpr.2021.09.264)
Response: As per the valuable suggestion, the mentioned references have been incorporated and highlighted in the revised manuscript.
Author Response File: Author Response.pdf
Reviewer 2 Report
1. For the Fig. 1, I suggest the author make a new figure for the schematic on the click chemistry on the self-assembly of MOF, not only the formation of MOFs. It is meaningless.
2. The Figure 3 is also meaningless, you can list a Table on the synthesis method.
3. The Table 2 is so trivial, please simplify it.
4. In the introduction, the authors have illustrated “scientists have made great strides to manufacture various MOFs and the exploration of their use in numerous scientific domains, including energy storages, medicinal technology, environmental pollution, sensing platforms, and catalysis, photocatalysis, oxidation, hydrogenation, drug delivery, bioimaging due to their diverse active sites. Some more updated refs may be considered, such as Micropor. Mesopor. Mat, 341(2022) 112098; Inorganics, 10(2022) 202; Molecules, 27(2022), 7166; New J. Chem., 2022, 46, 19577–19592 and CrystEngComm, 2022, 24, 6933–6943.
5. In the Table 2, the authors only list the examples, but not compared and analyzed them.
6. What are the key weaknesses/challenges in the field and how can current problems/limitations be solved? Are there any technical, technological, or methodical limitations that prevent research from advancing as it could?
Author Response
Dear Reviewer,
We are highly thankful to you for reviewing the manuscript and providing us your valuable suggestions and remarks for improvement of the manuscript. As per the suggestions received, the implementations have been carried out and the response for each query is given below:
All the changes have been highlighted as yellow text in the revised manuscript.
Reviewer
Recommendation: Minor revisions
Comments and Suggestions for Authors
Response: The suggestions provided by the reviewers will help us to improve the article and we are obliged to the reviewer for comments.
Response to comments:
- Comment: For the Fig. 1, I suggest the author make a new figure for the schematic on the click chemistry on the self-assembly of MOF, not only the formation of MOFs. It is meaningless.
Response: As per the valuable suggestions, the figure 1 has been redrawn, exhibiting the self-assembly of copper-based MOFs via the stitching of Cu(I) with linker and their subsequent application in ‘click’ synthesis of 1,2,3-triazoles and highlighted in the revised manuscript.
- Comment: The Figure 3 is also meaningless; you can list a Table on the synthesis method.
Response: As per the remarks, figure 3 has been omitted from the revised manuscript and instead, a table enlisting the reactions catalysed by different MOFs has been included in (table 3) and additionally a table containing detailed description of the different synthetic routes for MOF synthesis is included (section 4, table 2) and highlighted in the revised manuscript
- Comment: The Table 2 is so trivial, please simplify it.
Response: As per the suggestion, table 2 has been simplified by trifurcating it on the basis of utility (Table 5,6,7) of catalytic amount in the click reaction for the synthesis of 1,2,3-triazole derivatives.
- Comment: In the introduction, the authors have illustrated “scientists have made great strides to manufacture various MOFs and the exploration of their use in numerous scientific domains, including energy storages, medicinal technology, environmental pollution, sensing platforms, and catalysis, photocatalysis, oxidation, hydrogenation, drug delivery, bioimaging due to their diverse active sites. Some more updated refs may be considered, such as Micropor. Mesopor. Mat, 341(2022) 112098; Inorganics, 10(2022) 202; Molecules, 27(2022), 7166; New J. Chem., 2022, 46, 19577–19592 and CrystEngComm, 2022, 24, 6933–6943.
Response: As per the valuable remarks, the suggested references have been incorporated and highlighted in the revised manuscript.
- Comment: In the Table 2, the authors only list the examples, but not compared and analyzed them.
Response: As per the valuable recommendation, a comprehensive analysis was undertaken from the data compiled of different Cu-MOFs for catalytic applications in CuAAC and the observations have been discussed in detail in section 8 after figure 22 and highlighted in the revised manuscript.
- Comment: What are the key weaknesses/challenges in the field and how can current problems/limitations be solved? Are there any technical, technological, or methodical limitations that prevent research from advancing as it could?
Response: As per the valuable suggestion, the key weakness/challenges in the application of Cu-MOFs as catalyst in CuAAC with the mentioning of their microporous nature and stability; and their potential solutions have been discussed in section 9 and highlighted in the revised manuscript.
Author Response File: Author Response.pdf
Reviewer 3 Report
This review paper describes the role of copper-based metal-organic frameworks for click chemistry.
This paper requires major revision for the following concerns.
1. Table 2 should be adjusted wisely. It is taking up unnecessary space.
2. The manuscript requires extensive English editing.
3. The authors should add a new section in the manuscript along with a table describing the physical and chemical properties of the MOFs.
4. The authors should also mention the challenges in the preparation and application f copper-based MOFs.
5. The authors should also add a table describing the benefits/advantages such as the efficiency or robustness of copper-based MOFs for click chemistry over the other catalysts with references to the already published research in literature.
Author Response
Dear Reviewer,
We are highly thankful to you for reviewing the manuscript and providing us your valuable suggestions and remarks for improvement of the manuscript. As per the suggestions received, the implementations have been carried out and the response for each query is given below:
All the changes have been highlighted as yellow text in the revised manuscript.
Reviewer
Comments and Suggestions for Authors
This review paper describes the role of copper-based metal-organic frameworks for click chemistry.
Response: Authors are thankful for the suggestions and comments by reviewer.
Response to comments:
- Comment: Table 2 should be adjusted wisely. It is taking up unnecessary space.
Response: As per the valuable suggestion, table 2 has been adjusted by trifurcating it on the basis of utility (Table 5,6,7) of catalytic amount in the click reaction for the synthesis of 1,2,3-triazole derivatives.
2. Comment: The manuscript requires extensive English editing.
Response: As per the remarks, the language has been comprehensively improved throughout in the revised manuscript and highlighted.
3. Comment: The authors should add a new section in the manuscript along with a table describing the physical and chemical properties of the MOFs.
Response: As per the remarks, a new section 3 along with the table 1 enlisting various physico-chemical properties of metal organic frameworks has been added and highlighted in the revised manuscript.
4. Comment: The authors should also mention the challenges in the preparation and application of copper-based MOFs.
Response: As per the valuable suggestion, the challenges in the preparation and application of the copper-based MOFs due to their microporous nature, instability have been discussed in section 9 and highlighted in the revised manuscript.
5. Comment: The authors should also add a table describing the benefits/advantages such as the efficiency or robustness of copper-based MOFs for click chemistry over the other catalysts with references to the already published research in literature.
Response: As per the valuable suggestion, a table 4 has been incorporated in the revised manuscript containing various metals along with Cu-MOFs used to catalyse click reactions to analyse the robustness and efficiency of Cu-MOFs over other catalyst and highlighted in the revised manuscript.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
This work is well suited for publication in Catalysts
Reviewer 3 Report
The authors revised the manuscript following the reviewer's comments. The present form of the manuscript is better than before.
