Synthesis of (5Z)-3-Allyl-5-{[5-(4-methoxyphenyl)thiophen-2-yl]methylidene}-2-sulfanylidene-1,3-thiazolidin-4-one in L-Proline-Based Deep Eutectic Solvent

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This submitted paper describes the facile and high-yield synthesis of a rhodanine derivative with potential biological activity. It is synthesized with a simple Knoevenagel condensation using as a solvent a DES composed of proline and glycerol chosen on the basis of previous research by the authors. The target product was adequately characterized

In order to  strengthen the synthetic validity of this protocol, it would be appropriate to carry out  a reaction on a gram scale.

It would seem that three different types of DES are tested, however only the result of the reaction carried out in L-Proline/ ethylene glycol is reported. It would be appropriate to also report the results obtained with the other two types of DES.

The choice of tested solvents is linked to their viscosity. Have other DESs been tested with different Pro/EG ratios? What are the parameters that led you to choose the DES Pro/Eg over the other two? The authors should better justify this choice.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Hesse and co-workers report the synthesis of a rhodanine using an established strategy in a deep eutectic solvent. It is noted that the compound prepared may or may not be useful in several applications.

The synthesis is good. The characterization data are good. Although, I suggest that the m, 1H at 5.84 ppm could be reasonably described as a ddt.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Deep eutectic solvents（DESs）are expected to replace organic solvents and have been increased as the report for the synthesis of various compounds. The authors, S. Hesse et al., provided for the reaction of N-allylthiazolidinone and thiophenecarbaldehyde by using proline based DES to give the Knoevenagel condensation product in an excellent yield. The product is well characterized by NMRs, MS and IR. Furthermore, it is interesting that spectroscopic studies are also included.

I think the manuscript can be published on Molbank. Some small comments are below.

 

1.        All ‘E/Z’ configurations should be shown in the italic.

2.        Please remove the underline in the compound numbers.

3.        All spin-spin couplings ‘J’ should be shown in the italic.

4.        In the Abstract – please delete the half-space in front of (5Z)-3-allyl..., and the compound name should be shown in lowercase.

5.        Line 62 on page 2 and Line 126 on page 5 – please start the capital letter.

6.        Line 122 on page 5 – please delete the half-space between DMSO- and d₆.

7.        Line 133 on page 5 – please delete the hyphen between 10- and mL.

8.        Line 146 on page 5 – please unify the word font.

 

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors The authors in the revised version responded to my comments. The manuscript can now be published