Preparation of Dibenzofurotropones via Pd-Catalyzed Cyclization

Round 1

Reviewer 1 Report

The manuscript titled " Preparation of Dibenzofurtropones via Pd-catalyzed cyclization" reports a new approach for the preparation of dibenzo[2,3-b]furotropones via the palladium-catalysed oxidative addition of C-Br followed by C-H activation/cyclization.

Overall the manuscript is rich and interesting; and the paper structure is well-knit and suitable for publication in the journal, after minor revisions. The comments are listed as the following points:

1.              In title, “Dibenzofurtropones” should be “Dibenzofurotropones”

2.              In abstract, The abbreviation "DBU" must be specified.

3.              In introduction, “….exhibit an intriguing chemical and photophysical properties (Figure A1)” references must be added.

4.              In Figure A1, “[2,3-b]furotropne and [4,5-c]furotropne” should be “[2,3-b]furotropone and [4,5-c]furotropone”

5.              In Figure A2, “tribenzotropne, I” should be “tribenzotropone, I”

6.              In introduction, page 2, “…of dibenzo[2,3-b]furotropnes 1…” should be “…of dibenzo[2,3-b]furotropones 1….”.

7.              In section 3.3, line 2, “Spectroscopic data of all compounds in in ethanol…”, please delete "in”.

8.              Tables 2 and 3 have the same title. Please check.

9.              Please check the compound codes in Table 2, 1aa-1ga instead of 1-10.

10.           Title of Table 3 should be Spectral data of compound 1da.

Author Response

Response to reviewer 1
We would like to thank reviewer’s comments and corrections. Those comments are

all valuable and very helpful for the revision. The lists of changes are listed below.

1. In title, “Dibenzofurtropones” should be “Dibenzofurotropones”

Ans. Corrected accordingly

2. In abstract, The abbreviation "DBU" must be specified.

Ans. The full name of DBU is added. “1,8-diazabicyclo(5.4.0)undec-7-ene”

3. In introduction, “….exhibit an intriguing chemical and photophysical properties (Figure A1)” references must be added.

Ans. Added accordingly.

4. In Figure A1, “[2,3-b]furotropne and [4,5-c]furotropne” should be “[2,3-b]furotropone and [4,5-c]furotropone”

Ans. Corrected accordingly.

5. In Figure A2, “tribenzotropne, I” should be “tribenzotropone, I”

Ans. Corrected accordingly.

6. In introduction, page 2, “…of dibenzo[2,3-b]furotropnes 1…” should be “…of dibenzo[2,3-b]furotropones 1….”.

Ans. Corrected accordingly.

7. In section 3.3, line 2, “Spectroscopic data of all compounds in in ethanol…”, please delete "in”.

Ans. Corrected accordingly.

8. Tables 2 and 3 have the same title. Please check.

Ans. Have corrected the title of table 3.

9. Please check the compound codes in Table 2, 1aa-1ga instead of 1-10.

Ans. Have corrected accordingly.

10. Title of Table 3 should be Spectral data of compound 1da.

Ans. Same the point 8.

Reviewer 2 Report

The authors present the preparation of dibenzofurtropones via Pd-catalyzed cyclization. The work is clearly presented and detailed.

The length of the manuscript is adequate and the scope of products is good. Compounds 1 and 2 apear to be novel and they are fully characterised.

The manuscript can be accepted after the following changes.

Comments:

-Table 1: I am surprised that all reactions have exactly the same duration (20 h). Was the reaction complete in all the cases? I believe that the lower yielding reactions maybe required longer times.

-"It is worth mentioning that compound 2ag with para bromo substituent in Ar2 ring provided 1ad in 7% and a mixture of unidentified products under the optimized reaction conditions." Why was this compound not included in the scheme?

-"2.4. Spectroscopic Characterization": the authors should give all the experimental details and not only data on 2 compounds.

-the supporting information file is of good quality.

Author Response

Response to reviewer 2

We would like to thank reviewer’s comments and suggestion. Those comments are

valuable and helpful. The lists of changes are listed below.

1. Table 1: I am surprised that all reactions have exactly the same duration (20 h). Was the reaction complete in all the cases? I believe that the lower yielding reactions maybe required longer times.

Ans. Because the reactant was consumed within 20 h. We added a footnote to this table.

2. "It is worth mentioning that compound 2ag with para bromo substituent in Ar2 ring provided 1ad in 7% and a mixture of unidentified products under the optimized reaction conditions." Why was this compound not included in the scheme?

Ans. It is shown in Equation 1 because the obtained compound is identical to that of 1ad form 2ad.

3. "2.4. Spectroscopic Characterization": the authors should give all the experimental details and not only data on 2 compounds.

Ans. All other compounds are deposited in SI

4. the supporting information file is of good quality.

Ans. Thanks.

Round 2

Reviewer 1 Report

The authors considered most of the suggestions of reviewers and made the appropriate changes, so their work is enriching and can be published in Reactions.

Reviewer 2 Report

The manuscript can now be accepted.