N′-(3-Bromo-7-oxo-7H-benzo[de]anthracen-9-yl)-N,N-dimethylimidoformamide
Round 1
Reviewer 1 Report
Inthis contribution the authors describe the synthesis of the title compound as well as its photophysical properties in a series of 6 solvents. It should be noted that the same team has already described an regioisomer of with compound with the amidine group in position 3 (Luminescence 2018, 33, 1217). Nevertheless the title compound is new and this short note is therefore in the scope of the journal. I recommend the publication of this short note after correction/addition of the following points.
1- In elemental analysis results, I am surprised to have experimental % of Br. Indeed analysis was performed on CHNS-analyzer. The difference between calculated and measured % C in higher to the tolerated 0.4% difference. I would therefore recommend to add spectroscopic data (if possible high resolution) for this compound.
2- 13C NMR data should be performed. The copy of NMR spectra should be provided in ESI
3- Why two singlet are observed for the two methyl group of NMe2: I would have thought both were magneticaly equivalent.
4- In compound name (for example in the title), H and N should be in itallic (N’-(3-Bromo-7-oxo-7H-benzo[de]anthracen-9-yl)-N,N-dimethylimidoformamide. Please check for all compound names within the manuscript.
4- A reference should illustrate the sentence l 29/31 (ref 12?)
5- l46/47: What was the reaction time/temperature for the synthesis of previously cited analogues?
6- Table 1: Please add the polarity for each solvent (eg according to the Reichardt polarity scale)
7- l 78/79: Stokes shifts are better expressed as wavenumber difference (in cm-1)
8- Figure 1: It would be better to plot the molar absorption coefficent ε versur wavelength instead of absorbance versus wevelenfth.
9- l 117: please correct the molecular formula (digits should be in subscript)
Author Response
Response to the Comments from the reviewer
Point 1: In elemental analysis results, I am surprised to have experimental % of Br. Indeed analysis was performed on CHNS-analyzer. The difference between calculated and measured % C in higher to the tolerated 0.4% difference. I would therefore recommend to add spectroscopic data (if possible high resolution) for this compound.
Response 1: Elemental analysis data were previously obtained on an old analyzer, therefore they have such an inaccuracy. We re-performed elemental analysis, the results of which were added to the manuscript (Lines 122-123).
Point 2: 13C NMR data should be performed. The copy of NMR spectra should be provided in ESI
Response 2: 13C NMR data have been added (Lines 120-121). The NMR spectra are given in the prepared supplementary file.
Point 3: Why two singlet are observed for the two methyl group of NMe2: I would have thought both were magneticaly equivalent.
Response 3: For us, this is also an interesting result. Apparently, some difference between the methyl groups arises as a result of the electronic effects of the amidine group.
Point 4: In compound name (for example in the title), H and N should be in itallic (N’-(3-Bromo-7-oxo-7H-benzo[de]anthracen-9-yl)-N,N-dimethylimidoformamide. Please check for all compound names within the manuscript.
Response 4: All fixed.
Point 4: A reference should illustrate the sentence l 29/31 (ref 12?).
Response 4: The reference was added - [11] (Line 31).
Point 5: 46/47: What was the reaction time/temperature for the synthesis of previously cited analogues?
Response 5: The sentence was added: For 3-aminobenzanthrone and 2-bromo-3-aminobenzanthrone, a reaction temperature of 100-110ºC and a time of at least 3 hours are required [10].
Point 6: Table 1: Please add the polarity for each solvent (eg according to the Reichardt polarity scale)
Response 6: The polarities and the corresponding reference [13] have been added.
Point 7: 78/79: Stokes shifts are better expressed as wavenumber difference (in cm-1)
Response 7: The Stokes shift was recalculated in cm-1 (Line 80).
Point 8: 117: please correct the molecular formula (digits should be in subscript).
Response 8: Done.
We thank the Reviewer for the comments which allowed to improve the quality of our manuscript.
Round 2
Reviewer 1 Report
The authors have efficiently solved the point I raised. The manuscript is now suitable for publication.
