4,4-Difluoro-3-(3-phenylisoxazol-5-yl)-8-trifluoromethyl-5-(naphthalen-2-yl)-4-bora-3a,4a-diaza-s-indacene
Round 1
Reviewer 1 Report
“4,4-Difluoro-3-(3-phenylisoxazol-5-yl)-8-trifluoromethyl-5-(naphthalen-2-yl)-4-bora-3a,4a-diaza-s-indacene”
The article describes the synthesis and characterization of a new fluorophore BODIPY, in 62% yield, through the P2O5-promoted condensation of 2,2,2-trifluoro-1-[5-(naphthalen-2-yl)-1H-pyrrol-2-yl]-ethan-1-ol (2) with 3-phenyl-5-(1H-pyrrol-2-yl)isoxazole (3), followed by the oxidation and complexation with BF3. The authors shows that the presence of a naphthyl and 3-phenylisoxazolyl substituents give to the new fluorophore BODIPY extended conjugation and interesting photophysical characteristics.
Globally, the manuscript is well written, and the introduction is adequate to the described compound. The experimental procedure is clear, and the characterization data is in accordance with the synthesized compound.
Although the procedure for the synthesis of all new compounds is clear, the explanation of the synthesis of precursors 2 and 3 has not very clear in the main text. The paragraph concerning to this description must be improved.
If I am not misleading compounds 2 and 4 are new, as I can conclude by the characterization data, but there are no data for these compounds in the supplementary material. NMR spectra of all new compounds must be provided, or if are not new, the reference must be included in the description of the compound.
NMR 11B data of compound 1 should be provided.
In the NMR description of compounds 1, 2 and 4, the authors assigned of the proton and fluorine atoms. To make these attributions, is necessary to carry out the two-dimensional NMR spectra of the compounds. However, in the supplementary material there is no information about these spectra.
The authors have some explanation for the low quantum yield and short fluorescence life-time of compound 1 in MeCN?
Author Response
Reviewer wrote:
Although the procedure for the synthesis of all new compounds is clear, the explanation of the synthesis of precursors 2 and 3 has not very clear in the main text. The paragraph concerning to this description must be improved.
Answer:
The conditions for the synthesis of precursors 2 and 4 were added to text. Compound 3 was obtained according to the method described in paper 16. The conditions for its synthesis are given in Scheme 2b. Experimental details are given in the experimental part.
Reviewer wrote:
If I am not misleading compounds 2 and 4 are new, as I can conclude by the characterization data, but there are no data for these compounds in the supplementary material. NMR spectra of all new compounds must be provided, or if are not new, the reference must be included in the description of the compound.
Answer:
NMR spectra of compounds 2 and 4 were added in the supplementary material.
Reviewer wrote:
NMR 11B data of compound 1 should be provided.
Answer:
Done as recommended.
Reviewer wrote:
In the NMR description of compounds 1, 2 and 4, the authors assigned of the proton and fluorine atoms. To make these attributions, is necessary to carry out the two-dimensional NMR spectra of the compounds. However, in the supplementary material there is no information about these spectra.
Answer:
The two-dimensional NMR spectra of the compounds 1 and 2 were included in the supplementary material.
Reviewer wrote:
The authors have some explanation for the low quantum yield and short fluorescence life-time of compound 1 in MeCN?
Answer:
Unfortunately, at the moment we cannot explain why compound 1 has a low quantum yield and short fluorescence life-time in MeCN, research in this direction is under way.
